Preface: Wiring around the starter motor was butchered up by the PO.

I'm dealing with two situations here - marrying the M41 4-pin harness to the mother ship via the 4-pin disconnect on the engine bay side of the firewall just to the left of the heater box, and at the same time straighten out some "modified" wiring to the starter.

Since the car WAS a BW35 auto, the starter was inhibited by the park/neutral switch. So that means the blue wire from pin #50 on the starter switch was routed through the 4-pin disconnect, then down to the trans. But for an M41 configuration, the wiring diagram shows the blue wire running from pin #50 on the starter switch to the starter via a disconnect somewhere enroute. But I don't know if it's the aforementioned 4-pin disconnect or not, because they call ALL disconnects "#23" (big help).


So now I'm wondering if anyone with a properly-wired M41 could tell me:

1.) How does the blue wire, from Pin #50 on the starter switch, route to the starter?

2.) Does it route through the 4-pin disconnect?

3.) Looking at at the upper half of the 4-pin disconnect (male), what color wires are connected and their positions?

4.) Looking at at the lower half of the 4-pin disconnect (female), what color wires are connected and their positions?

5.) How are the two white D-jet wires (#37 for the cold start relay and #18 to the brain I think) integrated with the blue wire to the starter?

Many thanks!

Which style of reverse light switch do you have and is it working?

Do you have both male and female plugs for the transmission side of the neutral/safety harness?

--
Eric
Hi Performance Automotive Service (formerly OVO or Old Volvos Only)
Torrance, CA 90502

I think I have it worked out.

The one and only (unmolested) harness coming up from the trans consists of:

Yellow = Stalked-switched power to the O/D solenoid (No O/D relay on '73 ES is my understanding)
Brown = Power to both the Neutral switch and Reverse Light switch
.75 mm White = Neutral switch to Seat Belt Buzzer
1.0mm White = Reverse switch to Backup Lights

All four of the above wires run from the trans up to the 4-pin disconnect. That means there was no pin available in the disconnect by which to feed the START signal from #50 on the Starter switch. (In the BW35 configuration there are only there wires running from the trans to the 4-pin disconnect. Thus, a blue wire carries the signal from #50 on the ignition switch, THROUGH the 4th contact in the 4-pin disconnect, then down to the starter solenoid and two white D-Jet wires.)

So my plan is this: The trans-side of the 4-pin connector (Yellow/Brown/.75 White/1.0 White) will remain as-is, no re-pinning. I will re-pin the mothership side of the disconnect to make all four of the wires do what they should, relative to the trans harness. So the disconnect will only carry trans-related stuff.

In order to get the START signal from ignition switch to the starter and the D-jet wires, I have added a single pin disconnect that I cannibalized from the BW35 harness blue wire, and it sits right beside the 4-pin disconnect. So now the blue wire comes from #50 on the ignition switch, through the firewall, as it always did, but now terminates at the top of the new single-pin disconnect. I used the bottom half of the single-pin disconnect to join the blue wire running on to the starter plus the two D-jet wires. It's all sheathed and/or shrink wrapped and looks pretty clean. I still need to run a new yellow wire from the top of the 4-pin disconnect, through the firewall, and to the O/D stalk switch, but I have that under control.

If anyone has been able to follow all this gobblelty-goop, I'm grateful and impressed.

Thanks.