No physical progress at this stage, but have had success in getting a wiring diagram for the Auto, at least a wiring diagram from a Patrol. I'm feeling a lot more comfortable now about splicing the wiring looms rather than replacing (which would be a huge job, and would require some splicing anyway).
From the diagram below, you can see that most of the wiring is between the computer and the auto box, with only a limited number of connections to other units in the car (shown in yellow); namely:
*Throttle Position Sensor & Switch
*Revolution Sensor
*Overdrive switch
*Tacho
*Reversing Lamp (from the t-bar really)
*Starter Motor (what happens if you try and start an engine with the auto in D?)
*O/D and A/T Temp lamps on the dash
*Three fuses for various power connections
This diagram is not exactly right for the auto and computer I have, as the TD27T does not have its own ECU, so is probably for one of the petrol engines, but should give me enough of an idea that I can work it out form here. The speedo is also a mechanical drive, so no separate speedo sub unit as per the diagram. Mine also doesn't have cruise control or a Datalink connector (I think) , so they too are crossed out.
I've seen a reference to the tacho being driven from the EGR computer too, so I'll have to see how I connect that up, but I can live without a Tacho - have for the last 4 yrs anyway.
Anyone got any idea what sort of values the fuses might be?
On the dash I have there are also lamps for each position of the auto selector (PRND12 etc)
From the diagram below, you can see that most of the wiring is between the computer and the auto box, with only a limited number of connections to other units in the car (shown in yellow); namely:
*Throttle Position Sensor & Switch
*Revolution Sensor
*Overdrive switch
*Tacho
*Reversing Lamp (from the t-bar really)
*Starter Motor (what happens if you try and start an engine with the auto in D?)
*O/D and A/T Temp lamps on the dash
*Three fuses for various power connections
This diagram is not exactly right for the auto and computer I have, as the TD27T does not have its own ECU, so is probably for one of the petrol engines, but should give me enough of an idea that I can work it out form here. The speedo is also a mechanical drive, so no separate speedo sub unit as per the diagram. Mine also doesn't have cruise control or a Datalink connector (I think) , so they too are crossed out.
I've seen a reference to the tacho being driven from the EGR computer too, so I'll have to see how I connect that up, but I can live without a Tacho - have for the last 4 yrs anyway.
Anyone got any idea what sort of values the fuses might be?
On the dash I have there are also lamps for each position of the auto selector (PRND12 etc)
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