dash repair - now no start - which harness?
#1
Intermediate
Thread Starter
dash repair - now no start - which harness?
Have been busy repairing the 928 during lockdown - including repairing the dash which involved removing the pod, center console and dash for repair
As a side note, replaced existing radio and amplifier with a new SQR46 model and repaired internal 14 pin connector for the memory seats and mirrors. All works well
I also repaired the ignition switch - which seems to be working well
The car now cranks fine but does not start - so the obvious item is that it is likely ive not connected a wiring harness somewhere. Would there be an obvious candidate start with?
Couple of other symptoms - head lights no longer work and dash warning lights are not showing
Any ideas where to start with this? btw 1987 S4
As a side note, replaced existing radio and amplifier with a new SQR46 model and repaired internal 14 pin connector for the memory seats and mirrors. All works well
I also repaired the ignition switch - which seems to be working well
The car now cranks fine but does not start - so the obvious item is that it is likely ive not connected a wiring harness somewhere. Would there be an obvious candidate start with?
Couple of other symptoms - head lights no longer work and dash warning lights are not showing
Any ideas where to start with this? btw 1987 S4
#2
Team Owner
well its something you did what did you fix on the ignition switch? Did you take the switch apart?
You might have to put in a new ignition switch
You might have to put in a new ignition switch
#3
Intermediate
Thread Starter
Yes, could be the iginition switch but have no way sourcing a new one currently due to the current lockdown
Can these be tested somehow?
Also just fixed the headlights symptom - but still won't start
Have just found this unused connector by the CE panel - does this go anywhere?
Can these be tested somehow?
Also just fixed the headlights symptom - but still won't start
Have just found this unused connector by the CE panel - does this go anywhere?
#4
Team Owner
does the connector have a letter on it?
It might be from the alarm computer
post a picture of the full CE panel please
It might be from the alarm computer
post a picture of the full CE panel please
#5
Intermediate
Thread Starter
I don't note that on the far right of the CE panel connectors there is a broken brown/white wire - but i cant find the other end of it. No idea how long this has been broken
#6
Rennlist Member
Third 53 relay from the right on the top row is not oriented correctly. Looks mashed and the cover is clocked wrong.
I'd start there. It's the fuel pump relay.
I'd start there. It's the fuel pump relay.
#7
Intermediate
Thread Starter
Also - just found a harness not connected at the AC button.
Would this effect starting?
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#8
Intermediate
Thread Starter
The more I think about this - the more I think it's a bad ignition switch as I'm not hearing the fuel pump at all
Have checked both the fuel pump relay and the fuel pump fuse and they are both working fine
Is there anyway to jump the ignition system to start the fuel pump to test this?
Have checked both the fuel pump relay and the fuel pump fuse and they are both working fine
Is there anyway to jump the ignition system to start the fuel pump to test this?
#9
Intermediate
Have been busy repairing the 928 during lockdown - including repairing the dash which involved removing the pod, center console and dash for repair
As a side note, replaced existing radio and amplifier with a new SQR46 model and repaired internal 14 pin connector for the memory seats and mirrors. All works well
I also repaired the ignition switch - which seems to be working well
The car now cranks fine but does not start - so the obvious item is that it is likely ive not connected a wiring harness somewhere. Would there be an obvious candidate start with?
Couple of other symptoms - head lights no longer work and dash warning lights are not showing
Any ideas where to start with this? btw 1987 S4
As a side note, replaced existing radio and amplifier with a new SQR46 model and repaired internal 14 pin connector for the memory seats and mirrors. All works well
I also repaired the ignition switch - which seems to be working well
The car now cranks fine but does not start - so the obvious item is that it is likely ive not connected a wiring harness somewhere. Would there be an obvious candidate start with?
Couple of other symptoms - head lights no longer work and dash warning lights are not showing
Any ideas where to start with this? btw 1987 S4
#11
Rennlist Member
Mine starts and runs fine but the cluster is acting odd and the headlights don't work. Warning lights don't show during bulb check, backlighting is fine. Drove over a hard bump and the dash died all except the oil pressure. Comes back after restart. Pod connections are seated and solid. Need a place to start.
#12
The more I think about this - the more I think it's a bad ignition switch as I'm not hearing the fuel pump at all
Have checked both the fuel pump relay and the fuel pump fuse and they are both working fine
Is there anyway to jump the ignition system to start the fuel pump to test this?
Have checked both the fuel pump relay and the fuel pump fuse and they are both working fine
Is there anyway to jump the ignition system to start the fuel pump to test this?
I agree that your ignition switch is highly suspect since its the last key component that you worked on.
Separately, to bypass the fuel pump relay you will need a jump wire, a short wire with male spades of the same size as the relay's spades on either end, insert in to 30 and 87, that's left and right on the CE panel at the fuel pump relay slot. By jumpering the relay you will energize the fuel pump, so what that will tell you is that your fuel pump is functional but just not receiving voltage to operate, which points back to the ignition switch as a likely problem. If you just want to test the fuel pump relay itself then put it in the Horn slot, if the horn works then your relay is OK. FWIW, the current fuel pump relay "looking" like it is in the wrong way is just nothing, I don't think it can be put in any other way than the correct way; when removing relays the tops sometimes come off and are put back on, though not necessarily oriented in the correct direction.
#14
Rennlist Member
Does the car have a regular spark ? If not the fuel pump relay won't be energised. Don't be tempted to jump the FP relay, you could easily damage the LH ECU. Only substitute a known good relay in that position for fault finding.
Check for spark...
Check for spark...
#15
Intermediate
Thread Starter
Thanks for the great feedback
Car was running fine before Covid lock down - but I've tackled lots of small jobs during this time and the symptoms now appear to he unrelated
1) Headlights not working was a loose connection on the CE panel plug K - this problem is now resolved
2) Dash Warning lights not working - I believe this was a loose connection to AC switch in the centre console that i disturbed when putting in a new radio but i've yet to test this as I removed the dash cluster and haven't put it back yet
3) No start - I jumped the fuel pump on the CE as per the instructions and it works fine so Im adament its the iginition switch and i'm working on that today
4) Missing black plug connection - this looks very dusty and unused for sometime so I don't think it's related to anything and I certainly don't remember unplugging this at any stage. Might have been related to an alarm system as was suggested
5) The one peice I still would like to know is what is the brokem brown/white wire on plug W on the CE panel?
Great feedback - will keep the thread updated
Car was running fine before Covid lock down - but I've tackled lots of small jobs during this time and the symptoms now appear to he unrelated
1) Headlights not working was a loose connection on the CE panel plug K - this problem is now resolved
2) Dash Warning lights not working - I believe this was a loose connection to AC switch in the centre console that i disturbed when putting in a new radio but i've yet to test this as I removed the dash cluster and haven't put it back yet
3) No start - I jumped the fuel pump on the CE as per the instructions and it works fine so Im adament its the iginition switch and i'm working on that today
4) Missing black plug connection - this looks very dusty and unused for sometime so I don't think it's related to anything and I certainly don't remember unplugging this at any stage. Might have been related to an alarm system as was suggested
5) The one peice I still would like to know is what is the brokem brown/white wire on plug W on the CE panel?
Great feedback - will keep the thread updated