when I initially went into this problem it was starting, but I had noted that it wouldn't start in park, only neutral, then I realized the park-neutral switch was damaged so I swapped it and in doing so cleaned the contacts and greased them with a dab of electrical grease.

now it would stand to reason that's the area where things got messed up but it could be that the intermittent was not related and it's somewhere else and still haunting me.


I made a typo when describing my PNP switch above..

"I did take apart and swapped the park neutral switch , I replaced it just before this issue,
because it had broken when something fell in the valley and I moved the shifter but it tests ok Open circuit unless in park or neutral then coded circuit ."

- I meant to say I have continuity from key to park /neutral switch and back to the key, I unplugged the keyswitch and verified that i do have continuity(back to key) in park or neutral and no continuity if the shifter is in other positions. Im not suspecting the PN-switch to be the issue.

i checked all the fuses and I'll check them again. I did not pull the fuse tray. I did find that the solenod J had a bad contact, I pulled it and swapped it. and sprayed some cleaner down in the socket. it was clicking when I pressed on the top of it but that cleaning and swapped relay seemed to stop that from happening. both relays had a J on them.

pulling the console is always such a PITA , I think I was trying to take the screws out from inside that hold the side panels and really I may be able to pull both sides that surround the fuse tray as one piece. getting the radio out and a replacement in took a lot of disassembly in the area. I had a hard time releasing the radio.

if necessary I can pull that all back apart to inspect under the fuse tray. I do have the spare fuse tray, still connected to my spare harness for comparison.


maybe this service port is on the passenger side? I'm at work now but will check and also verify if I can see it on my 89 240 0r 89 740. If I can confirm what you mention on the other cars then I can look and verify if it's not there It may be in a different location, or may not be present on my model.

as noted the car with the issue is a bit earlier , using hall sensor in distributor whereas the later ones, in my other 2 cars used the TDC sensor instead, that might help verify when I'm on the right wiring diagram. that schematic I initially posted was for a newer 2.4 litre and that is wrong.

I do have the correct blue book parts book so it might show some details of the wiring harness. I can look into that.


the replacement PN-switch did have a different plug on the PN- switch wires so I soldered and spliced on the older connector but the wire colors were the same. funny I did note the backup lights weren't on, but I think that may be unrelated. its basically two switches and I verified the reverse one makes contact when in reverse. I don't think I confused the wiring between the two switches during my plug splicing.

since I'm a bit confused I figured I should remove my spare engine harness from that old engine and have a closer look at that one. I noted the 8 pin connector looked a bit dirty on both the spare harness and mine wouldn't separate easily. . If its in a sorry state I could replace it with a terminal block if I splice in a bit more wire length to do that. I'm ok doing a reliable solder heat-shrink and splice job.

I think I should find continuity back from that starter trigger wire, I think it's green with a blue stripe. I think it should go to the 8 pin plug and once I'm sure I'm on the right pin then I can follow that through my spare harness, I want to see if that wire terminates at the key switch, or where it does go (reverse engineering) if the triggger wire for the starter eventually terminates at the key then I must have power there..

I stuck a pin throgh each wire connected to the key, and tried all the positions on each wire and wrote out a little table for myself. the actual keyswitch plugs into the end of the harness at the key switch so I can swap key switches and I'm just turning it with a screwdriver so I have access to the wiring. the problem is not with the mechanics of the key, that's not electrical. I can unplug the keyswitch and access the ends of the harness wires there and there is some numbers to ID the wires on that connector.



right now I have that key switch poking out from under my speedo and the speedo reconnected.

I should be able to ohm out using the beep function on my meter and check if with key turned ( or switch removed) that I have continuity from the key lug to that 8 pin plug and then on to the green wire on the starter.

I know there is other wiring involved because when I turn the key this relay in the tray ( J) clicks, that seems to also indicate that there is some switching going on as I turn the key to start.

there is some circuitry that turns off the headlights during cranking. maybe that's what the J relay is doing.. this means the circuit is more complex than simply the key feeding power to the starter motor trigger.

if there is a relay that turns the lights off during cranking, then maybe it also has a contact involving this crank circuit?

Easily to become totally confused, and frustration and brain seize then sets in, so I need to break this into baby steps of troubleshooting. I though maybe verifying my way through from the starter back up into wherever it originates might help me understand why power isn't being fed to the starter trigger.. I think I might end up at the key if I follow it back but maybe some relay terminal is involved in the electrical path.. the wire loom isn't confusing, it could have a break but shouldn't be too complicated.. that's just a bunch of wire.

the key switch and its various functions such as dimming lights during cranking are very confusing.

It may or may not be normal that I have no wire at the key that is hot only when the key is in position 3 (cranking)

Phil