Hi guys. Thank you for the additonal help. Took the vehicle to the nearest landy specialist with a nanocomm. No communication to the ECU. The chap thinks that there may be a break in om of the ECU wires. He thinks this may possibly be causing the whole issue as the communication issues may cause issues with the system clearing the codes after the work was done... does this at all make sense? Does anyone have a wiring diagram for the obd harness?
Meldrew's mate
Member
In your first post you said...
From that I read that the car had no warning lights before it went into the garage, and those pesky Amigos lit when it came back (and not before).
As you don't have a fault code reader I assume this was done by the same garage.
@sierrafery asked you some pertinent questions that you appear to have dodged, trying to determine what actions you took whilst trying to diagnose, and to clarify what you did.
I doubt it, but if you're poking around blindly with jumper wires there's a high risk of doing some damage and compounding the problem.
As the car appeared to have no problems of the electrical system before it went to the garage, I doubt the 'broken ECU' theory. The OBD harness is (from the Haynes manual) fed with 12v from fuse F20 via the purple wire on pin 16 of the OBD socket, pins 4 and 5 go to earth, data comes from each of the control units (SLABS, SRS, Cruise control, ETC, BCU, etc.) onto pin 7 (pink).
Again from memory, I think that the OBD connector is connected to all these systems via the SLABS module. Could it be that attempts to find the previous fault(s) included disconnecting the SLABS connectors. Check the location and security of these plugs.
Check pin 7 of the OBD connector is in good condition.
MM
From that I read that the car had no warning lights before it went into the garage, and those pesky Amigos lit when it came back (and not before).
As you don't have a fault code reader I assume this was done by the same garage.
@sierrafery asked you some pertinent questions that you appear to have dodged, trying to determine what actions you took whilst trying to diagnose, and to clarify what you did.
I doubt it, but if you're poking around blindly with jumper wires there's a high risk of doing some damage and compounding the problem.
As the car appeared to have no problems of the electrical system before it went to the garage, I doubt the 'broken ECU' theory. The OBD harness is (from the Haynes manual) fed with 12v from fuse F20 via the purple wire on pin 16 of the OBD socket, pins 4 and 5 go to earth, data comes from each of the control units (SLABS, SRS, Cruise control, ETC, BCU, etc.) onto pin 7 (pink).
Again from memory, I think that the OBD connector is connected to all these systems via the SLABS module. Could it be that attempts to find the previous fault(s) included disconnecting the SLABS connectors. Check the location and security of these plugs.
Check pin 7 of the OBD connector is in good condition.
MM
Hello MM.
I didnt dodge the question, when it comes to electrical testing i have left it to my truck mechanic at work and i have been waiting for an answer from him. I have checked the obvious mechanical things but electrics arent my beat subject.
The lr specialist we saw today seemed convinced that there is any issue with the obd harness hense why i was asking for a wiring diagram to see where it tracks.
I didnt dodge the question, when it comes to electrical testing i have left it to my truck mechanic at work and i have been waiting for an answer from him. I have checked the obvious mechanical things but electrics arent my beat subject.
The lr specialist we saw today seemed convinced that there is any issue with the obd harness hense why i was asking for a wiring diagram to see where it tracks.
Meldrew's mate
Member
Can't help you with posting an OBD diagram, my IT skills aren't up to that, but see previous post from me for info on the power and data pins of the OBD socket. Your electrical geezer should be able to make sense of that.
Again, I doubt that a broken ECU wire is to blame, though it seems that to continue you must achieve OBD comms.
MM
Again, I doubt that a broken ECU wire is to blame, though it seems that to continue you must achieve OBD comms.
MM
meego
Well-Known Member
Logical head now, it wasn't there before so it must be something they have done! They have replaced front brakes and suspension so the hubs would have been off. So I am thinking replace both front hubs, rings and sensors to see if the problem goes away? Or a cheap ECU in case they have fried that but I would have thought if that was the case the vehicle wouldn't start?.
Thank you in advance.[/QUOTE]
I can't think why the hubs would have been off to do this ?? That's not to say they couldn't have damaged the abs sensor leads though !!
Thank you in advance.[/QUOTE]
I can't think why the hubs would have been off to do this ?? That's not to say they couldn't have damaged the abs sensor leads though !!
sierrafery
Well-Known Member
Hi, did that electrician use a diagnostic tool which is fuly compatible with the D2 Td5 ? ...cos if it was some generic OBDII tool that might not communicate without being an issue on the data link ...
that's another suspect thing which makes me think he doesnt know what's about cos each ECU is connected separately from a dedicated menu of the scantool so you can' just suggest it's one ECU or another eventually just the one which doesnt comunicate cos it's quite unlikely to be two faulty ECUs at the same time, there are 4 ECUs on a D2 (5 if it's auto), which one doesnt communicate???... IMO you are on the wrong path
sierrafery
Well-Known Member
The fact that the diagnostic socket has power doesnt mean that the data link is OK as well... and what kind of tool was used if it's not a secret? ... it seems that you are convinced that those two ECUs are ''fried'', do you mean that the scan tool had no comms with the SLABS nor with the ECM but it had comms with the other ECUs?
+1 - the number of fully compatible tools for a D2 is quite small
.... How much experience of D2's did this autoelectrician have ?
sierrafery
Well-Known Member
That would mean that all the ECUs on the vehicle are dead as long as there is feed in the port as you said?... i dont want to insist against specialists but are you sure they checked continuity of the data link from OBD port's pin 7 and the related pins of all the ECUs?... cos i doubt that somebody went to header C0286 which is a nightmare to reach as it's wrapped into the main harness behind the fascia on the left side
I have just messaged him to check. If there was an issue that would lead back to wiring issues causing no comms?. Its turnung into a nightmare getting this sorted. Also i forgot to mention in my update that on top of the 3 amigos and handbrake light the box is locked in 3rd gear when in D and has m and s flashing on the dash a D flashing on the box
sierrafery
Well-Known Member
The only thing which can cause a complete lack of communication of a proper tester with ALL the ECUs (which means "the vehicle") is an interruption between OBD port pin 7 and pin 15 of that header... the 3 amigos are triggered by the SLABS ECU and the flashing M+S by the autobox ECU, the engine ECU (which i presume your electrician named "main") is not even involved in these
i've seen cases when the receptacle in the OBD port pin 7 was loose
i've seen cases when the receptacle in the OBD port pin 7 was loose
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sierrafery
Well-Known Member
the SLABS needs programming while the autobox ECU is plug and play but it's good to reset addaptive values in it so tester is needed anyway... though i really doubt that the ECUs are at fault
sierrafery
Well-Known Member
IMO first of all you should be certain that it's not a data link issue cos if it's that you can buy all the ECUs in vain... there are rare cases when an ECU fails as to not communicate at all while if it's that the other ECUs would communicate without problems
sierrafery
Well-Known Member
I'll help you but you need RAVE for the connector views...do you have it? ...if not say again what year is your D2
