Last night I re checked the earth on the APPS. With the engine running, operating the throttle and with key on engine not running, working the APPS through its range there's 15mV across the earth pin on the APPS and the bat' neg' terminal. Would this be enough to cause problem?

I wasn't sure so I thought I would add an extra known good earth. Autodata doesn't have a wiring diagram for the 3 plug system on a 306, Only the single plug system. The nearest I can find is a 307 but I'm slightly suspicious of its accuracy and don't trust it. I checked the wiring diagram and (assuming its right) the earth goes through the ECU. I presume this is just for convenience and ease of wiring as the loom just goes to one place? is there any other reason.

So does any one have a correct diagram for the 306 with this 3 plug ECU? Is the 15mV across the earth too much? How do I go about correcting this? Any other idea's?

Cheers.
Steve.