keep research

Suspect earth problem on the dash or instrument cluster on my EF.

Problem 1. is my speedo needle is not working and the tranny is locked in safe mode. The transducer is ok as I have swapped it for one that is working.

Problem 2 is the brake switch fail circuit has 12 Volts but very low amperage as though a bad earth exists. The brake switch diode tested ok.

Both power supplies come from the instrument cluster.

I have been told that there is an earth that gives trouble and it is a mongrol to get at. It is apparantly located in the centre of the dash near the dimister. Has anyone had this problem before or do you know where this earth connection is. Thanks.

Might even consider changing the instrument cluster over.

keep research

Ok...seems no-one answered my call I will reply to myself.

The problem was an electrical storm Spiked the ECU and the instrument cluster processors. There was no visual signs of lightning or any burnt smell ...just the units were tested and were dead. Both were replaced under insurance.

The speedo needle was a part of the instrument cluster problem. The signal from the tranny sensor goes to the instrument processor. As the processor was dead, the tranny went into Limp Home Mode (locked in third gear).

In terms of the low amperage coming through the Brake fail circuit....It turned out being the bulb filaments that acted as a resister thus reducing the current. So this was OK. Thanks.

thefonz

Sorry we didn't help you, but I'm glad you got it fixed.