can it run on ESP32?

[vfebert]

Hi, was really happy to find this one, intending to do a "My own CO2 footprint" project. Could you please help me in providing an Arduino example running on an ESP32 - which has Bluetooth build in. When I compile the sample sketch, it simply gives "serial3 unknown" error. Sorry for being only a hobby programmer....

[sabifa]

+1 would also like to know :)

I've tried to combine the example code here and your posted comment in this thread and come up with this:

#include "BluetoothSerial.h"
#include "ELMduino.h"

#define ELM_BT SerialBT
#define ESP_BLUETOOTH_NAME "ESP32"

BluetoothSerial SerialBT;
ELM327 myELM327;

void setup()
{
  pinMode(LED_BUILTIN, OUTPUT);
  digitalWrite(LED_BUILTIN, HIGH);

  Serial.begin(115200);
  ELM_BT.begin(ESP_BLUETOOTH_NAME, true);

  Serial.println("Attempting to connect to ELM327...");

  if (!ELM_BT.connect("OBDII"))
  {
    Serial.println("Couldn't connect to OBD scanner");
    while (1);
  }

  myELM327.begin(ELM_PORT);

  Serial.println("Connected to ELM327");
  Serial.println("Ensure your serial monitor line ending is set to 'Carriage Return'");
  Serial.println("Type and send commands/queries to your ELM327 through the serial monitor");
  Serial.println();
}

float rpm = 0;

void loop()
{
  float tempRPM = myELM327.rpm();

  if (myELM327.status == ELM_SUCCESS)
  {
    rpm = tempRPM;
  }
  else
  {
    Serial.print(F("\tERROR: "));
    Serial.println(myELM327.status);
    delay(100);
  }
}

I couldn't test it yet because I do not have my esp32 and OBD adapter here yet but maybe you can test it and report back @vfebert.

I guess we have to replace ELM_BT.connect("OBDII") with the actual MAC address of the adapter.

[PowerBroker2]

When I compile the sample sketch, it simply gives "serial3 unknown" error.

Yeah, the current example isn't very portable and isn't general enough. I'll update the example to be easier to understand and add a separate example for the ESP32.

I guess we have to replace ELM_BT.connect("OBDII") with the actual MAC address of the adapter.

Actually, no. The .connect() method is overloaded to handle several different input arguments. If the input is a String, the ESP32 will decipher the input as the remote device's name. If the input is a uint8_t array, it will decipher the input as the remote device's MAC address. The name of my ELM327 happens to be "OBDII" and I figured it would be easiest to use the name as opposed to trying to find the ELM327's MAC address.

In the end, it's all up to how you want to connect to the ELM327.

[PowerBroker2]

I haven't done extensive testing of the library in it's current state, but I should be able to get some testing done before the end of the week...

[PowerBroker2]

Should be fixed in release 1.1.4

[vfebert]

thanks so much guys - looking forward to 1.1.4 and promise to do some testing as much as my time allows.

[pniewiadowski]

I was trying to test this today. The connection with BT OBD2 was successful but then I've got some errors while trying to read the response.

This is what I got on serial monitor:

19:05:21.539 -> ets Jun 8 2016 00:22:57 19:05:21.539 -> 19:05:21.539 -> rst:0x1 (POWERON_RESET),boot:0x13 (SPI_FAST_FLASH_BOOT) 19:05:21.539 -> configsip: 0, SPIWP:0xee 19:05:21.539 -> clk_drv:0x00,q_drv:0x00,d_drv:0x00,cs0_drv:0x00,hd_drv:0x00,wp_drv:0x00 19:05:21.539 -> mode:DIO, clock div:1 19:05:21.539 -> load:0x3fff0018,len:4 19:05:21.539 -> load:0x3fff001c,len:1216 19:05:21.539 -> ho 0 tail 12 room 4 19:05:21.539 -> load:0x40078000,len:9720 19:05:21.573 -> ho 0 tail 12 room 4 19:05:21.573 -> load:0x40080400,len:6352 19:05:21.573 -> entry 0x400806b8 19:05:23.706 -> Attempting to connect to ELM327... 19:05:49.302 -> Connected to ELM327 19:05:49.302 -> Ensure your serial monitor line ending is set to 'Carriage Return' 19:05:49.302 -> Type and send commands/queries to your ELM327 through the serial monitor 19:05:49.302 -> 19:05:49.302 -> Received: ?> 19:05:49.302 -> RPM: 0 19:05:49.302 -> Header NOT found

Do you know what can it be?

[PowerBroker2]

@pniewiadowski Can you post your entire sketch?

Regardless, thanks for testing - I'll do some debugging myself today and/or tomorrow and get back to all of you.

[PowerBroker2]

I did some testing today and was able to get both my ESP32 to connect to my ELM327 and successfully query telemetry (RPM and speed) using the ELMduino library.

Although I didn't have to change any parsing logic, I did do some updates to the library. If you're still having trouble, please try reinstalling/updating the library, post your entire sketch, and post example printouts from the Serial Monitor.

[Sowmya-Sukhanand]

@PowerBroker2 Hii,even i tried today updating/reinstalling the library and then running the code with ESP32 and OBD2 via bluetooth MAC address.Iam not able to get the output.It is just printing(In Debug Mode)

Received:?> HEADER NOT FOUND RPM:0

Please help me with this!!!The header file is not detectable Should i send any commands via serial monitor to init the OBD?

The code that iam running

include

//#include "ELMduino.h"

include

BluetoothSerial SerialBT; int i = 0; //String MACadd = "30:ae:a4:fe:ff:5e"; uint8_t address[6] = {0x00, 0x1d, 0xa5, 0x68, 0x98, 0x8c}; String name = "OBDII"; // <------- set this to be the name of the other ESP32!!!!!!!!! char *pin = "1234"; bool connected; ELM327 elm; uint32_t rpm = 0;

void setup() { Serial.begin(115200); SerialBT.begin("ESP32testm", true); Serial.println("The device started in master mode, make sure remote BT device is on!");

if(!SerialBT.connect(address)){ Serial.println("Not Connected"); while(1); } if (!elm.begin(SerialBT)) { Serial.println("Couldn't connect to OBD scanner"); while (1); } Serial.println("Connected"); }

void loop() { float tempRPM = elm.rpm(); if (elm.status == ELM_SUCCESS) { rpm = (uint32_t)tempRPM; Serial.print("RPM: "); Serial.println(rpm); } else { Serial.print(F("\tERROR: ")); Serial.println(elm.status); delay(100); } }

[PowerBroker2]

You seem to be connecting to the ELM327 fine, but it doesn't seem to understand the rpm query for some reason. Can you use a Bluetooth Serial Monitor app (android or laptop) to connect to the ELM327 and try the RPM query manually?

I don't have the problem with my device...strange

[PowerBroker2]

On second thought, you can use this instead to access the ELM327 through the Serial Monitor without a third party app:

#include "BluetoothSerial.h"

BluetoothSerial SerialBT;

#define DEBUG_PORT Serial
#define ELM_PORT   SerialBT

void setup()
{
  pinMode(LED_BUILTIN, OUTPUT);
  digitalWrite(LED_BUILTIN, HIGH);

  DEBUG_PORT.begin(115200);
  ELM_PORT.begin("ESP32test", true);

  DEBUG_PORT.println("Attempting to connect to ELM327...");

  if (!ELM_PORT.connect("OBDII"))
  {
    DEBUG_PORT.println("Couldn't connect to OBD scanner");
    while(1);
  }

  DEBUG_PORT.println("Connected to ELM327");
  DEBUG_PORT.println("Ensure your serial monitor line ending is set to 'Carriage Return'");
  DEBUG_PORT.println("Type and send commands/queries to your ELM327 through the serial monitor");
  DEBUG_PORT.println();
}

void loop()
{
  if(DEBUG_PORT.available())
  {
    char c = DEBUG_PORT.read();

    DEBUG_PORT.write(c);
    ELM_PORT.write(c);
  }

  if(ELM_PORT.available())
  {
    char c = ELM_PORT.read();

    if(c == '>')
      DEBUG_PORT.println();

    DEBUG_PORT.write(c);
  }
}

[pniewiadowski]

The first sketch I was testing came from this repo example: https://raw.githubusercontent.com/PowerBroker2/ELMduino/master/examples/ESP32_test/ESP32_test.ino This is the output of serial monitor:

19:05:21.539 -> ets Jun 8 2016 00:22:57 19:05:21.539 -> 19:05:21.539 -> rst:0x1 (POWERON_RESET),boot:0x13 (SPI_FAST_FLASH_BOOT) 19:05:21.539 -> configsip: 0, SPIWP:0xee 19:05:21.539 -> clk_drv:0x00,q_drv:0x00,d_drv:0x00,cs0_drv:0x00,hd_drv:0x00,wp_drv:0x00 19:05:21.539 -> mode:DIO, clock div:1 19:05:21.539 -> load:0x3fff0018,len:4 19:05:21.539 -> load:0x3fff001c,len:1216 19:05:21.539 -> ho 0 tail 12 room 4 19:05:21.539 -> load:0x40078000,len:9720 19:05:21.573 -> ho 0 tail 12 room 4 19:05:21.573 -> load:0x40080400,len:6352 19:05:21.573 -> entry 0x400806b8 19:05:23.706 -> Attempting to connect to ELM327... 19:05:49.302 -> Connected to ELM327 19:05:49.302 -> Ensure your serial monitor line ending is set to 'Carriage Return' 19:05:49.302 -> Type and send commands/queries to your ELM327 through the serial monitor 19:05:49.302 -> 19:05:49.302 -> Received: ?> 19:05:49.302 -> RPM: 0 19:05:49.302 -> Header NOT found

And it is keep looping display over and over same text: 19:05:49.302 -> Received: ?> 19:05:49.302 -> RPM: 0 19:05:49.302 -> Header NOT found

Now I took the above sketch: https://github.com/PowerBroker2/ELMduino/issues/3#issuecomment-587134687 and this is what I am able to see in serial monitor:

21:23:49.401 -> >ets Jun 8 2016 00:22:57 21:24:52.205 -> 21:24:52.205 -> rst:0x1 (POWERON_RESET),boot:0x13 (SPI_FAST_FLASH_BOOT) 21:24:52.205 -> configsip: 0, SPIWP:0xee 21:24:52.205 -> clk_drv:0x00,q_drv:0x00,d_drv:0x00,cs0_drv:0x00,hd_drv:0x00,wp_drv:0x00 21:24:52.240 -> mode:DIO, clock div:1 21:24:52.240 -> load:0x3fff0018,len:4 21:24:52.240 -> load:0x3fff001c,len:1216 21:24:52.240 -> ho 0 tail 12 room 4 21:24:52.240 -> load:0x40078000,len:9720 21:24:52.240 -> ho 0 tail 12 room 4 21:24:52.240 -> load:0x40080400,len:6352 21:24:52.240 -> entry 0x400806b8 21:24:54.375 -> Attempting to connect to ELM327... 21:25:16.826 -> Connected to ELM327 21:25:16.826 -> Ensure your serial monitor line ending is set to 'Carriage Return' 21:25:16.863 -> Type and send commands/queries to your ELM327 through the serial monitor 21:25:16.863 ->

PS. I repeated test with example ESP32_test.ino sketch, after updating to latest ELMduino library - same situation. PS2. In both sketches I have to comment out this two lines:

//pinMode(LED_BUILTIN, OUTPUT);
//digitalWrite(LED_BUILTIN, HIGH);

[PowerBroker2]

Hmm, interesting.

Can you try sending the following commands with this sketch?:

• AT E0
• AT SP 0
• 010D

Entering 010C into the serial monitor should return something like "010D 00" where 00 is your speed in hex in kph. Try that and let me know the results.

Also, make sure your serial monitor is in carriage return line ending mode!

[Sowmya-Sukhanand]

Thanks for the reply @PowerBroker2 . My question is that the header file itself is not detected.So what can be done for that?I have uploaded a snapshot of the code

[PowerBroker2]

It means you don't have the library installed...

[Sowmya-Sukhanand]

I do have the library installed with the latest version 1.1.7

I tried sending the AT commands via serial monitor and it works...but when i try it using library it doesnt!!!

[PowerBroker2]

In that case the header file is detected and compiled.

You might need to go into ELMduino.cpp to add some print statements to figure out what's going on. Without being there with you to test on your equipment there's not much I can do. It works with my ESP32 with my ELM327. If it's not working with your setup I'll need more info as to what exactly is going on with your hardware. For instance, is the library actually sending the AT commands? Can you confirm this with serial prints? Can you confirm the AT commands are formed properly? What is the exact response of the ELM327 for each AT command? Can you confirm it responds with "OK>"? etc, etc...

I'm more than happy to adjust the library so that all can easily use it, but I need very detailed testing results when I can't replicate the errors myself.

[Sowmya-Sukhanand]

There is no problem with the hardware,both esp32 as well as elm327 because they connect well via bluetooth also whenever i send AT commands via serial monitor to elm327 it responds appropriately. Anyways i'll confirm with the serial prints in the library to check if it is actually sending the commands or no.

[vfebert]

Hi, rainy sunday in Germany, means a bit of time to test. Purchased an original VEEPEAK BLE, installed 1.18, used the latest sketch from the above. Good news: got a connection, but unfortunately no ">" promt, so no answer to "AT E0" - happy to receive any comment that might help a hobby programmer..

[pniewiadowski]

@PowerBroker2 sorry for late response. I took the sketch you told me and this is the output of the serial monitor.

`ets Jun 8 2016 00:22:57 18:41:34.434 -> 18:41:34.434 -> rst:0x1 (POWERON_RESET),boot:0x13 (SPI_FAST_FLASH_BOOT) 18:41:34.434 -> configsip: 0, SPIWP:0xee 18:41:34.434 -> clk_drv:0x00,q_drv:0x00,d_drv:0x00,cs0_drv:0x00,hd_drv:0x00,wp_drv:0x00 18:41:34.478 -> mode:DIO, clock div:1 18:41:34.478 -> load:0x3fff0018,len:4 18:41:34.478 -> load:0x3fff001c,len:1216 18:41:34.478 -> ho 0 tail 12 room 4 18:41:34.478 -> load:0x40078000,len:9720 18:41:34.478 -> ho 0 tail 12 room 4 18:41:34.478 -> load:0x40080400,len:6352 18:41:34.478 -> entry 0x400806b8 18:41:36.645 -> Attempting to connect to ELM327... 18:42:01.471 -> Connected to ELM327 18:42:01.471 -> Ensure your serial monitor line ending is set to 'Carriage Return' 18:42:01.471 -> Type and send commands/queries to your ELM327 through the serial monitor 18:42:01.471 -> 18:42:22.251 -> AT E0 OK

18:42:22.290 -> >AT SP 0 OK

18:42:32.296 -> >010D SEARCHING... UNABLE TO CONNECT

18:42:41.259 -> >010D SEARCHING... UNABLE TO CONNECT`

[PowerBroker2]

@vfebert Since your OBD scanner module is a BLE version, you'll have to use the ESP32's BLE capability. Currently, my example is only for normal Bluetooth serial and will not work for BLE. That being said, I'm sure the ESP32 can make that BLE connection, I'll just have to do a little research on how that works. I hope that helps.

@pniewiadowski Did you do that test while the car was fully on and running?

[PowerBroker2]

@vfebert Take a look at this tutorial on ESP32 BLE. Since I don't have a BLE OBD scanner I can't do any real testing to modify my examples. Since you have one of those modules, can you do the testing to figure out how to get the ESP32 to connect to your BLE OBD scanner?

[pniewiadowski]

@PowerBroker2 yes, you were right. I have switch the ignition on and now I have this:

19:26:41.863 -> ets Jun 8 2016 00:22:57 19:26:41.863 -> 19:26:41.863 -> rst:0x1 (POWERON_RESET),boot:0x13 (SPI_FAST_FLASH_BOOT) 19:26:41.863 -> configsip: 0, SPIWP:0xee 19:26:41.863 -> clk_drv:0x00,q_drv:0x00,d_drv:0x00,cs0_drv:0x00,hd_drv:0x00,wp_drv:0x00 19:26:41.863 -> mode:DIO, clock div:1 19:26:41.863 -> load:0x3fff0018,len:4 19:26:41.863 -> load:0x3fff001c,len:1216 19:26:41.863 -> ho 0 tail 12 room 4 19:26:41.863 -> load:0x40078000,len:9720 19:26:41.863 -> ho 0 tail 12 room 4 19:26:41.863 -> load:0x40080400,len:6352 19:26:41.900 -> entry 0x400806b8 19:26:44.031 -> Attempting to connect to ELM327... 19:27:09.312 -> Connected to ELM327 19:27:09.312 -> Ensure your serial monitor line ending is set to 'Carriage Return' 19:27:09.312 -> Type and send commands/queries to your ELM327 through the serial monitor 19:27:09.312 -> 19:27:15.089 -> AT E0 OK

19:27:15.089 -> >AT SP0 OK

19:27:18.881 -> >010D SEARCHING... 7E8 03 41 0D 00

Seems it is connecting and receiving data.

[miguelos6]

@vfebert I think this project is using BLE https://hackaday.io/project/167968-rear-car-speedometer

@pniewiadowski - that's an output from Serial Monitor sketch, right ? did you manage to get results from example sketch using rpm query ?

@PowerBroker2 - for me it seems everyone is able to connect & get data using simple Serial Monitor sketch, but not the example ESP32_test. Also - I tried to connect using MAC and int values : //if (!ELM_PORT.connect("001DA520BC21")) //if (!ELM_PORT.connect("127324437537")) if (!ELM_PORT.connect("V-LINK")) only the last one seem to work

Another thing - when I tested the ESP32_test in version <2.0 I was getting the same as @pniewiadowski, see :

Header NOT found RPM: 0 Received: 410C0BBC

Header NOT found RPM: 0 Received: 410C0BC6

Header NOT found RPM: 0 Received: 410C0BC3

that seems to be an issue in the function/calculation itself, right ? With 2.0 I receive only 0 values all the time

RPM: 0

Don't have that much time to test with car, but maybe I'll try and modify CPP to print serial output here & there to tell you more maybe when I manage to start obdsim on rpi I could test it while sitting at home

BTW - should we configure BT PIN for connection ?

[miguelos6]

Ok I managed to start odbsim on win10 and tested it working with Torque (Android) - proved to work. Still querying it with rpm funtion from ELMduino it behaves weird - displays only value when it's changed in obdsim, then zeroes it out, check below (don't bother for DPF prints, these are my custom functions)

18:18:25.177 -> load:0x40078000,len:8896 18:18:25.177 -> load:0x40080400,len:5816 18:18:25.177 -> entry 0x400806ac

18:18:25.177 -> load:0x40080400,len:5816 18:18:25.177 -> entry 0x400806ac 18:18:26.572 -> Attempting to connect to ELM327... 18:18:35.451 -> Connected to ELM327 18:18:38.765 -> RPM: 0 18:18:38.765 -> DPF soot %: 0 18:18:38.765 -> DPF stat: 0

18:19:01.559 -> RPM: 1417 18:19:01.559 -> DPF soot %: 0 18:19:01.559 -> DPF stat: 0 18:19:03.902 -> RPM: 0 18:19:03.902 -> DPF soot %: 0 18:19:03.902 -> DPF stat: 0 18:19:06.186 -> RPM: 0 18:19:06.186 -> DPF soot %: 0 18:19:06.186 -> DPF stat: 0

18:19:35.836 -> RPM: 1557 18:19:35.836 -> DPF soot %: 0 18:19:35.836 -> DPF stat: 0 18:19:38.088 -> RPM: 1557 18:19:38.088 -> DPF soot %: 0 18:19:38.088 -> DPF stat: 0 18:19:40.410 -> RPM: 0 18:19:40.410 -> DPF soot %: 0 18:19:40.410 -> DPF stat: 0 18:19:42.676 -> RPM: 0 18:19:42.676 -> DPF soot %: 0 18:19:42.676 -> DPF stat: 0

[PowerBroker2]

Don't try testing the custom PIDs until you get RPM working.

Simply run the example for ESP32 with the library version 2.0.0 and let me know what happens.

[miguelos6]

@PowerBroker2 👍 seemed I was trying too much, and it was failing always because other things were added. With running engine & just by changing OBD name it works :

09:15:18.900 -> ets Jun 8 2016 00:22:57 09:15:18.900 -> 09:15:18.900 -> rst:0x1 (POWERON_RESET),boot:0x13 (SPI_FAST_FLASH_BOOT) 09:15:18.900 -> configsip: 0, SPIWP:0xee 09:15:18.900 -> clk_drv:0x00,q_drv:0x00,d_drv:0x00,cs0_drv:0x00,hd_drv:0x00,wp_drv:0x00 09:15:18.900 -> mode:DIO, clock div:1 09:15:18.900 -> load:0x3fff0018,len:4 09:15:18.900 -> load:0x3fff001c,len:1044 09:15:18.938 -> load:0x40078000,len:8896 09:15:18.938 -> load:0x40080400,len:5816 09:15:18.938 -> entry 0x400806ac 09:15:19.705 -> Attempting to connect to ELM327... 09:15:42.185 -> Connected to ELM327 09:15:42.329 -> ERROR: 7 09:15:42.477 -> ERROR: 6 09:15:42.722 -> ERROR: 7 09:15:42.970 -> ERROR: 7 09:15:43.080 -> RPM: 0 09:15:43.118 -> ERROR: 6 09:15:43.371 -> ERROR: 7 09:15:43.592 -> RPM: 1004 09:15:43.667 -> RPM: 996 09:15:43.773 -> RPM: 995 09:15:43.881 -> RPM: 991 09:15:43.956 -> RPM: 1007 09:15:44.069 -> RPM: 1002 09:15:44.182 -> RPM: 1007 09:15:44.256 -> RPM: 1003

[pniewiadowski]

@PowerBroker2 unfortunatelly the ESP32 example doesn't work for me. ERROR: 7 - this is what I got:

16:33:18.053 -> ets Jun 8 2016 00:22:57 16:33:18.053 -> 16:33:18.053 -> rst:0x1 (POWERON_RESET),boot:0x13 (SPI_FAST_FLASH_BOOT) 16:33:18.053 -> configsip: 0, SPIWP:0xee 16:33:18.089 -> clk_drv:0x00,q_drv:0x00,d_drv:0x00,cs0_drv:0x00,hd_drv:0x00,wp_drv:0x00 16:33:18.089 -> mode:DIO, clock div:1 16:33:18.089 -> load:0x3fff0018,len:4 16:33:18.089 -> load:0x3fff001c,len:1216 16:33:18.089 -> ho 0 tail 12 room 4 16:33:18.089 -> load:0x40078000,len:9720 16:33:18.089 -> ho 0 tail 12 room 4 16:33:18.089 -> load:0x40080400,len:6352 16:33:18.089 -> entry 0x400806b8 16:33:20.246 -> Attempting to connect to ELM327... 16:33:42.581 -> Connected to ELM327 16:33:42.723 -> ERROR: 7 16:33:42.982 -> ERROR: 7 16:33:43.227 -> ERROR: 7 16:33:43.476 -> ERROR: 7 16:33:43.731 -> ERROR: 7 16:33:43.962 -> ERROR: 7 16:33:44.210 -> ERROR: 7 16:33:44.468 -> ERROR: 7 16:33:44.715 -> ERROR: 7

[PowerBroker2]

@miguelos6 Glad it's working for you!

@pniewiadowski It's fairly common for the ELM327 to have errors in its response for a short amount of time after booting. Let it run for 60 seconds and if it still gives you an error. Can you verify you're using release 2.0.0 and testing with the car on and running?

[vfebert]

got it running on my ESP32 together with VEEPAK BLE and a C-Class Mercedes. Thanks you very much for V 2.0.0

[miguelos6]

@vfebert got anything more but rpm ?

[PowerBroker2]

@vfebert Could you please post your code? I'd like to incorporate BLE into the library (or at least an example)

[vfebert]

will do as soon as I wrote some lines. So far, I have only used the sample code posted above, and queried throught the Arduino serial monitor: fuel tank level, for example works fine.

[PowerBroker2]

You were able to connect to it via Bluetooth serial or did you have to modify the example for BLE? I'm interested only in how you were able to connect the ESP32 to the BLE OBD scanner (if that makes sense).

[vfebert]

did not (yet) modify the sample code. Typed in the commands into the Arduino serial monitor. Works pretty well ! Right now I am modifying the code to automatically transfer data from the Veepak into MQTT (home automation). Seemed to have been a good idea to buy an original OBD dongle: https://www.veepeak.com/product/obdcheck-ble/

[Sowmya-Sukhanand]

@PowerBroker2 Thanks for the library updation.The obd works!!!

[hepetry]

I really liked your library, where I used your example on an ESP32 card and it worked immediately. Unfortunately I'm not a programmer, and I would like to add the PID's (04 ENGINE_LOAD), (17 THROTTLE_POSITION) (99 ENGINE_REFERENCE_TORQUE). I started with PID 04, changing the example as shown below and had a strange response. Can you help me?

/////////////////////////////////////////////////////// Load
  if (myELM327.queryPID(34, 4))
  {
    int32_t tempLoad = myELM327.findResponse();

    Serial.print("Engine Load: ");
    for (byte i = 0; i < PAYLOAD_LEN; i++)
      Serial.write(myELM327.payload[i]);
    Serial.println();

    if (myELM327.status == ELM_SUCCESS)
    {
      load = tempLoad;
      Serial.print("Load: "); Serial.println(load);
......
  }

the answer I got was: Connected to ELM327 RPM: 843 Engine Load: 7F2211 load: 0

[PowerBroker2]

Try using

• myELM327.queryPID(SERVICE_01, ENGINE_LOAD)
• myELM327.queryPID(SERVICE_01, THROTTLE_POSITION)
• myELM327.queryPID(SERVICE_01, ENGINE_REFERENCE_TORQUE)

inside your if-statements for each query

[hepetry]

it worked perfectly .. thank you very much !!!

[george0305]

Regarding the ESP32, i used it for two weeks now with the elm32 obd and it worked fine. Thank you for that! However, for a few days now it stopped connecting and i get the Phase 2 error. I can find the elm and esp on phone`s bluetooth. What can it possibly be?

[PowerBroker2]

When you look on you phone, what's the name of the ELM327? Is it "OBDII"? Also, what version of the library are you using? Are you using the latest release?

Can you post your sketch?

[george0305]

Thank you for your time, yes, on my phone its OBDII. I checked that. The version is 2.0.7, i had it implemented in the car for 2 weeks and everything went fine until now. I didnt change anything, just let it run. Yesterday i recompiled and uploaded but still the same problem. Below is the connection part, the one in your example and i added a display: ` ... Serial.begin(115200); display.begin(SSD1306_SWITCHCAPVCC, 0x3C); // required to run SSD1306

ELM_PORT.begin(ESP_BLUETOOTH_NAME, true);

Serial.println("Attempting to connect to ELM327...");

  display.clearDisplay();
  display.setTextSize(1);
  display.setTextColor(WHITE);
  display.setCursor(10, 20);
  display.println("Connecting...");
  display.display();

if (!ELM_PORT.connect("OBDII")) { Serial.println("Couldn't connect to OBD scanner - Phase 1"); while (1); }

if (!myELM327.begin(ELM_PORT)) { Serial.println("Couldn't connect to OBD scanner - Phase 2"); while (1); }

Serial.println("Connected to ELM327");

`

[PowerBroker2]

There have been several bug fixes since that release. Try using release 2.0.10 and see if it fixes things for you.

[george0305]

Hi, so i updated the library and i tested. Results: -Still not connecting by itself but i managed to get it connected like so:

• pair the phone with the OBDII
• unpair the phone
• restart the ESP32
• it connects. From what i can see, im not sure and possibly be wrong, its not pairing or its waiting for the pairing pin. I tried to search how the bluetooth serial connects and i tried a setpin but no success. Can it be an ELM327 problem? If so, i can try tomorrow or on Monday to get a new one.

[PowerBroker2]

The problem might lie in the fact that your phone is paired. Because of this, the ELM might be bound to the phone without allowing your Arduino to connect to it. Try turning off bluetooth for all other devices (including your phone) and then see if the Arduino can connect to the ELM.

[george0305]

I tried it, i dont usually leave bt on, so that isnt the option. If i manage to connect it to the elm by the steps above and then restart the esp, it wont reconnect to the elm (phone bt off).

[PowerBroker2]

Bizzare, you might need to go into the library's function int8_t ELM327::sendCommand(const char *cmd) (cpp file) and add print statements to determine what (if anything) is being returned by the ELM327 when being configured by the Arduino.

[george0305]

Ok, i will try to test it and i will come back these days. Thank you a lot!

[vfebert]

my 2 cents on function: Last version 2.0.10 works without any issues on my end. Again, BIG THANKS

1 smartphone bluetooth always off when testing

2 have spend 30$ on a good adaptor from Veepeak, not over Amazon, directly from manuf to avoid getting a bad clone. Nice overview here: https://www.carscanner.info/choosing-obdii-adapter/ (and no, I am not working for that company ;-)

3 trying to be close to the adaptor (means: sitting in my car with the laptop testing). Reason: from 5meter away, I got a connection (took longer), but no data.

hope this helps?

[PowerBroker2]

Thanks @vfebert! Since it seems to be working for the vast majority of everyone (including BLE users apparently), I'm going to close this issue. If anyone still has issues, please make a new issue for your individual problem and I'll get to it as soon as I can.