auto to manual swop speedo pickup

PurpleSnow · Post by **PurpleSnow** » 02 Apr 2018, 22:06

Hi there

im new to the volvo scene. I bought a 94 850 t5 abt 2 weeks ago and I have been searching high and low
to sort out the speedo. Ive been looking on the gearbox for the plug but cant find any pickup. only the reverse
on the top according to my searching I think i have a m56 gearbox in. the guy i bought it from says it was an auto
I found a 2 pin red plug on the gearbox side with grn/ye and ye/brn wire and according to wiring diagram that is
speedometer sensor.

Now my Q is how do get the speedo to work if it was a manual swop.

Post by **tryingbe** » 03 Apr 2018, 11:09

Vin number will tell you if the 850 was auto or manual from the factory.

If the car was manual swapped, and the transmission was from a later model 850, all you have to do is ID the vehicle speed sensor wiring from the car, cut the VSS connector off, extend the speed sensor wiring (2 wires, signal and ground), and splice it to the driver side ABS wiring (2 wires, signal and ground). Use the multi-meter to figure out which of the two wires of the VSS is ground and signal, and do the same ABS wiring.

PurpleSnow · Post by **PurpleSnow** » 04 Apr 2018, 09:55

so if i understand correctly i take the 2 wires that was connected on the gearbox speed sensor and splice them into the driver side abs sensor wiring. and that will work.

is there gearboxes that dont have speed sensors on the box itself
do they pickup from the abs sensors

sorry i know these questions are bit stupid

PurpleSnow · Post by **PurpleSnow** » 04 Apr 2018, 09:57

oh and ive looked around and i dont think this was a auto to manual swop. i just think it is a swop due to failure or something. i cant find anything that tell me it was a auto previously.

skloon · Post by **skloon** » 04 Apr 2018, 10:10

The earlier gearboxes had a built in speed sensor- later ones didn't the abs sensor is fine to use

PurpleSnow · Post by **PurpleSnow** » 05 Apr 2018, 11:56

tnanx for all the help guys. will try that over the weekend and give update

PurpleSnow · Post by **PurpleSnow** » 07 Apr 2018, 13:14

ok i spiced the wires to the drivers side abs sensor. earth and sensor as far as i can figure.
but still no speedo reading. I have been seing the abs light since i got the car. should I swop out sensors from pass side and see what happens.

PurpleSnow · Post by **PurpleSnow** » 08 Apr 2018, 12:15

ok my bad one wire didnt have comms all the way for some reason. it works now, ill just double check with gps tomorrow.
now all the functions work on the car.

another question regarding the odo the small gear inside the cluster running the odometer. can you get that or should i opt to maybe 3d print it. dont think i will be able to find a cluster for parts here.

Post by **scot850** » 08 Apr 2018, 13:19

The odometer gears can be bought for not a huge amount. There are 2 or 3 vendors out there. FCP Euro used to list it and I think IPD also. The manufacturer also sells direct I think.

https://www.ebay.com/itm/VOLVO-850-ODOM ... 1168921107

https://www.ipdusa.com/products/4710/10 ... meter-gear

https://www.fcpeuro.com/products/volvo- ... ed-850gear

Last 2 are the cheapest.

There is also a couple of Youtube videos on how to fix.

Neil.

AaronsVolvo · Post by **AaronsVolvo** » 08 Apr 2018, 13:51

I do not want to question what you are doing, but what other problems does your car have?
You said the ABS light is on, any other lights?
It may be something else causing your speedo to stay dead, not necessarily poor wiring.

I could be wrong though.