Speed sensor connection

caheyne · Post by **caheyne** » 26 Jan 2021, 05:05

Does anyone have a clue which two wires go to the speed sensor? I do have a replacement with different color codes! And where do the two leftover of the 4wire connector wires go? See attachment pictures. 2006 V70
Thanks, Caesar

Post by **firstv70volvo** » 26 Jan 2021, 17:23

The connector with the 4 wires cut looks like the it might be the connector for the two transmission speed sensors. Can you check the wires coming from the two transmission sensors and see if it's these wires? The two transmission sensors are on top the transmission, one is near the back near the firewall and the other is towards the front and end of the transmission near the right wheel well. What's the the story with the cut wires?

https://www.eeuroparts.com/Parts/434425 ... e%20150%2B

caheyne · Post by **caheyne** » 27 Jan 2021, 02:11

Yep, I know for sure the connector with the 4 wires, 2 of those wires have to be connected to the transmission sensor. I've found one but, as you can see in the pictures, the wires have been nibbled off by rodents so I can not determine the color code and the replacement connector (picture) have different color codes. Rats, squirrels or whatever tried to build a nest under the hood. Most of the 15 wires are color-coded so I know how to connect them again. Only the 4 wire connector is a puzzle. I know 2, but which ones and the other 2, I have no clue. So you're saying there are 2 transmission speed sensors? I'll look for the second one. I attached some more pictures to make the story clear. Hmm, can't add a picture in my reply?

Post by **firstv70volvo** » 27 Jan 2021, 09:00

caheyne wrote: ↑27 Jan 2021, 02:11 Yep, I know for sure the connector with the 4 wires, 2 of those wires have to be connected to the transmission sensor. I've found one but, as you can see in the pictures, the wires have been nibbled off by rodents so I can not determine the color code and the replacement connector (picture) have different color codes. Rats, squirrels or whatever tried to build a nest under the hood. Most of the 15 wires are color-coded so I know how to connect them again. Only the 4 wire connector is a puzzle. I know 2, but which ones and the other 2, I have no clue. So you're saying there are 2 transmission speed sensors? I'll look for the second one. I attached some more pictures to make the story clear. Hmm, can't add a picture in my reply?

Yes, there's two transmission speed sensors, input speed sensor and output speed sensor. Input is the one towards the front of the car, output in back, see photo.

From the 2002 wiring diagram pins 1 and 2 of the four pin connector go to the input speed sensor and 3 and 4 go to the output speed sensor. Both the sensors are the same so hopefully one of the connectors to the sensor has enough wire remaining to determine the color coding to the two pins on the sensors. There's a - and + for the two pins going to the sensors; pin 1 yellow with black strips is the - signal for the input speed sensor and the yellow with the red stripe is the + signal for the input speed sensor. Pin3 is the - signal and pin 4 is the + signal for the output speed sensor.

From the connector photo I can't tell the color coding going to the two pin connectors so not sure what's - and +. The back output speeds sensor may have more wire to figure out the color coding and which is - and + on the sensor connectors. If we know one will know how the other because thery are the same sensor type.
The color coding in my wiring diagram matches for the input sensor but not the output sensor but I've seen color coding mistakes before in the wiring diagram before and it may be different for different model years. I think the four pin connector pinout is correct though so if we can determine how the two pin connection is connected we can wire both sensors correctly. My car doesn't have the two pin connectors for the sensors the wires go directly into the sensors so I can't verify how the two pin connectors should be wired.

: InkedTrans Sensors connector 4 wires_LI.jpg (1.5 MiB) Viewed 5532 times

caheyne · Post by **caheyne** » 27 Jan 2021, 10:53

Wow, that's very useful information! Thanks a lot. I'll be back in FL in about 2 weeks and try to connect everything! I'll keep you posted!

Post by **firstv70volvo** » 27 Jan 2021, 18:11

caheyne wrote: ↑27 Jan 2021, 10:53 Wow, that's very useful information! Thanks a lot. I'll be back in FL in about 2 weeks and try to connect everything! I'll keep you posted!

If you have a multimeter you can use the diode setting to measure the two sensors and determine if they are wired correctly to the four pin connector. If you don't have multimeter then you'll have to use the color coding from the wire insulation of the old connectors. It looks like the rats chewed the one connector down so far you can't see the the stripe color of the insulation so you'll have to look at the other speed sensor connector to see if there's enough wire insulation for a color code check. If you have a multimeter I'll attach some photos of the meter hookup and expected readings.

caheyne · Post by **caheyne** » 28 Jan 2021, 02:52

Please, yes I do have a multimeter! Thanks. And do you agree about the 15-17 leftover wires just connect them via color codes? And after I'm done, I'm gonna use anti rodent tape and spray anti rodent stuff under the hood regularly

caheyne · Post by **caheyne** » 28 Jan 2021, 03:26

How about: https://www.volvopartswebstore.com/prod ... 13725.html
maybe that's easier and sofar affordable?

Post by **firstv70volvo** » 28 Jan 2021, 13:46

caheyne wrote: ↑28 Jan 2021, 02:52 Please, yes I do have a multimeter! Thanks. And do you agree about the 15-17 leftover wires just connect them via color codes? And after I'm done, I'm gonna use anti rodent tape and spray anti rodent stuff under the hood regularly

I've attached photos showing the diode setting readings of the input and output shaft speed sensors. With these sensors there's a forward bias reading and reversed bias reading that should be able to confirm proper wire connections. I have sensors and a wiring harness off a 2004 S60 AW55-51sn transmission that I used in the photos. I also included my wire splicing for the transmission valve body solenoids wire harness because I purchased the transmission used and they cut the wiring harness. I did have some problems with a two of wires with what looked like identical color coding on the insulation. I never installed the used transmission so I don't know if I did all the wiring splicing correctly but I did measure everything from the plugs to the solenoids and it all looked good.

For the 15-17 wires you have to reconnect can you determine if all the color coding of the wires is unique for each of the wires and has a matching wire to connect to?

There's also the salvage yard as a option to find another wiring harness if needed.

caheyne · Post by **caheyne** » 30 Jan 2021, 07:18

Hmm, it looks like my reply from 2 days ago disappeared? I'll try again.
Thanks for the pictures. I think I'll go with a new harness (around $60 including shipping) but it's very helpful to have this information.
I'm gonna use the same solder connectors for the color coded wires!
In Florida there are not so many V70's on the salvage yards, I did find zero in my neighborhood. I'm in Amsterdam right now and due to COVID rules the salvage yards are closed. I'll be back in Fl in 2 weeks. I'll keep you posted.
Thanks again for your help!