Planning the next
AO Silver Member
Join Date: May 2007
Location: United Kingdom
What you need to do is remove the main instrument pack ( speedo & rev counter ). Undo the two allen screws, drop the steering column down and ease it out.
On connector A ( should be the white one on the left ) find pin 7. The pin number is moulded into the connector near the wire entry holes. You can disconnect the connector from the instrument pack. Once you've found pin 7, double check by looking at the wire colour. It should be pink.
Set your multimeter to resistance and stick the black probe on the car body. Measure the resistance on pin 7.
Now you have to remember roughly how much fuel you have in the tank!
The resistances for the displayed levels are as follows :
Full : 0 to 6 Ω
3/4 : 59 to 69 Ω
Half : 116 to 126 Ω
1/4 : 186 to 201 Ω
At reserve : 262 Ω
Empty : 295 to 315 Ω
If the resistance you get agrees with what you think the tank has got in it, you have now isolated the problem to the gauge itself, the logic in the speedo cluster or the wiring between the two instrument clusters.
The wiring between the clusters can be checked by looking for continuity between pin 13 on the main instruments and the supplementary fuel gauge connector ( wire is blue ).
If the warning light isn't working as well as the gauge, that points to the main instrument pack having a fault in its fuel sender logic. If the warning light works and the wiring between the instruments is OK, it's the fuel gauge you need to look at.
N.B. Just to add, for anyone looking at the above in future, this process does not work for phase 2 & 3. Phase 2 & 3 are wired differently.
Last edited by pkr; 30-11-11 at 07:34.