• Hello Guest, welcome to the initial stages of our new platform!
    You can find some additional information about where we are in the process of migrating the board and setting up our new software here

    Thank you for being a part of our community!

need a guru!

clarda

Member
Joined
Aug 22, 2008
Location
Dahlonega, Ga.
ok. i have an 84 (1/2) 242dl m46. this thing has a factory installed 1031 diff with the 12
window speed sensor. i put in an m47 just to get it going. i'd like to hook up an electric speedo that i have, but the speed sensor wiring (1 brown/ 1 blue) go to a little black box left of the clutch pedal. i've only been able to identify it as "control unit" by googling the part #. WHAT THE HELL IS THIS THING?! I'M BAFFLED. i've never worked on an 84 w/ 1031 before. the car doesnt have cruise and no abs. what would this thing need speed signal for?
i can pull the terminals out of the connector for my speedo, but is this thing important? i can get a picture tomorrow if needed. the p# is 1324877. any info would be great thanks guys, Dave.
 
could this be like a lamda timer or something?

Sounds like it. The lambda sond replacer reminderer is a black box with two wires and a dinky cable that goes in the back of the 84's mechanical speedometer. It won't have anything to do with your new electronic speedometer mod.

However, if you don't have some helpful folks ahead of you on this electronic cluster retrofit, I can imagine you'll have a few other compatibility issues to look forward to. No place better than here, though, to get them sorted out.
 
thanks art, this actually has 7 wires in it though. termination is set up like 5 pin relay but w/ 2 small pins over 31 and 1. this car is very odd. the only difference i could find between cable and e-speedo is power delivery to voltage regulator from speedo vs. external power (if i read the schematic right:oops:). i'll plug away some more later tonight when the shop clears out maybe. open to any suggestions on this mystery box...
 
Last edited:
Well, it can't be what I said it was, then. Dave, you did say this was a 242dl (dl not a turbo) but any relay that would use a terminal "1" would be connected to ignition coil minus, so maybe not for fuel like on k-jet, but shift indicator for the M46.

It has two wires that sense the speedometer rotation where the cruise usually does, and like you say, 7 terminals. The purpose is to light the "up arrow" when it is time to move the shifter. Not an essential function in my view.

Another thing bothers my sense of knowing what you have. Because electronic speedometer didn't arrive until 86, the notion of a factory installed diff with tone ring and sender is, well, not ringing right.
 
Last edited:
having started working on these at the dealer in the 90's, i also always thought the same. many people on tb have said the same as i thought. but sure enough i have an 84.5 ym w/ 1031 original to the car. harness and diff were installed on the assembly line (for some reason i have a tendency to aquire the oddities). i do think you are probably dead on with the shift indicator box:oops: the longer i look at this damn thing the more i remember them. never had to replace one i guess...
 
harness and diff were installed on the assembly line

How much of the harness was there? Are you saying the gray cable came up through the plate for the tank access, and then ends there, or is it actually connected and run to the front of the car that came with a mechanical speedometer?

I learn something every day, and I can only guess maybe the rear axles were already being made for the 7 series, or some such reasoning, so Volvo installed electronic-equipped differentials as a matter of convenience? Even 85's in the US still had the mechanical speedometers.
 
yes, this is a 2 rib 1031,e-speedo diff and the harness runs upto the shift indicator cont. unit. this car brakes all the rules of logic
 
yes, this is a 2 rib 1031,e-speedo diff and the harness runs upto the shift indicator cont. unit. this car brakes all the rules of logic

Actually, this is depicted in the manual, and it was staring me in the face, but my stubborn brain refused to accept the logic of it. Gaaah. I knew I shouldn't have clicked anything saying "guru."

Allow me to atone by scanning the drawings I wasn't looking at carefully.

85wdm112.jpg


85wdm113.jpg
 
Back
Top