Replaced the sender unit in the diff and the speedo still isn't working
The voltages all seem correct right up to the speedo, until I connect the sender unit
Then the earth and 2 live wires seem to swap polarity when the engine is running.
thanks speedy I'll check for a resistor. Mind you, the console from the Silverstone did exactly the same when I put it in the V6 as a trial. Everything worked except the speedo.
Been thinking about this again. I'm gonna check the earth. I have a funny feeling I did find something strange, but didn't pay attention at the time.
Will test and reroute the earth tonight and see what happens.
The +ve to the speedo gives 12v when the ignition is on, but the engine isn't running.
The signal wire to the speedo gives no voltage when in this same state.
The tests at the plug where the sensor joins to to the wiring loom also give the correct results.
When the engine is running, the +ve gives 0v and the signal wire gives 12v, even when the car is standing still
There isn't any tests for voltages when the engine is running in the manual. But somehow I think I have a wiring or ECU fault
The injector light gives the code: 1-2-5-1 - control unit EPROM
thanks JB, I knew if I held off long enough you'd come to the rescue
I will rewire the speedo circuit if it isn't the gearbox drive. I have a funny feeling that the sensor isn't getting a voltage when the engine is running. The sensor gets it power from pin 1 on plug A of the instrument cluster. This goes dead when the engine is running, but is OK when just the ignition is on. I think I'll do temp rewire before the drill test as with no voltage, the sensor wouldn't work anyway............hmmmmmmm.........a chance to tinker again !!!!!