Hello
I'd like to ask for some tips investigating a problem concerning link establishing to car's ECU via ODB in 2002 Clio 2 phase 2 K4J with Sirius 34 ECU (EOBD compliant).
For a month or so, since buying interface, i've been using an ELM327 bluetooth interface with Torque app quite a lot (while driving mostly) without any issues and one day, out of a sudden, it stopped working stating that it is unable to establish connection to ECU. There is no problem establishing BT link between handheld and ELM, it works fine. I checked the ELM on another car (for sever times to be sure) and it worked fine, as it used to on my drive.
On that day when things broke, i got into the car, plugged the ELM into OBD slot and after many retries Torque was still complaining about not being able to chat with ECU. So i disconnected it and set off for drive. After couple of minutes i stopped, repeated the procedure and while stationary the connection worked, unfortunately only to the point i started engine, then connection was gone and any further retries to connect since then failed. I'm not sure if it's of any significance to my particular problem but I recall a few situations where interface lost connection to ECU, while driving, but managed to reconnect instantly so I assumed it's just how it works and didnt' bother.
What I have already done to debug:
+disconnected battery and even ECU connector for several hours
+checked ODB port and ECU connector PINs - seemed ok
+measured voltage on OBD 4 and 16 pins - correct (12.6V on shut off engine)
+measured impedance between CANH and CANL lines on OBD port - 61ohms and not changing while hand playing with various wires
+checked all fuses
+before the problem emerged there were no DTCs set
One more strange issue: when engine is running and Torque is trying to make a link it checks various protocols sequentially - during those checks the engine RPM pointer shivers going to zero and back to normal for a couple of times (engine at this time runs smoothly).
What could have gone wrong, what else can I check to investigate? Any help appreciated.
I'd like to ask for some tips investigating a problem concerning link establishing to car's ECU via ODB in 2002 Clio 2 phase 2 K4J with Sirius 34 ECU (EOBD compliant).
For a month or so, since buying interface, i've been using an ELM327 bluetooth interface with Torque app quite a lot (while driving mostly) without any issues and one day, out of a sudden, it stopped working stating that it is unable to establish connection to ECU. There is no problem establishing BT link between handheld and ELM, it works fine. I checked the ELM on another car (for sever times to be sure) and it worked fine, as it used to on my drive.
On that day when things broke, i got into the car, plugged the ELM into OBD slot and after many retries Torque was still complaining about not being able to chat with ECU. So i disconnected it and set off for drive. After couple of minutes i stopped, repeated the procedure and while stationary the connection worked, unfortunately only to the point i started engine, then connection was gone and any further retries to connect since then failed. I'm not sure if it's of any significance to my particular problem but I recall a few situations where interface lost connection to ECU, while driving, but managed to reconnect instantly so I assumed it's just how it works and didnt' bother.
What I have already done to debug:
+disconnected battery and even ECU connector for several hours
+checked ODB port and ECU connector PINs - seemed ok
+measured voltage on OBD 4 and 16 pins - correct (12.6V on shut off engine)
+measured impedance between CANH and CANL lines on OBD port - 61ohms and not changing while hand playing with various wires
+checked all fuses
+before the problem emerged there were no DTCs set
One more strange issue: when engine is running and Torque is trying to make a link it checks various protocols sequentially - during those checks the engine RPM pointer shivers going to zero and back to normal for a couple of times (engine at this time runs smoothly).
What could have gone wrong, what else can I check to investigate? Any help appreciated.
