I found this lovely Photobucket album that has some great shots of the modified wiring harness after swapping in a M56. I wish I had found this much sooner!
http://s42.photobucket.com/user/ludeles ... t=3&page=1
95 850 M56 manual transmission Swap Write Up
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- Year and Model: 1995 Volvo 854 T-5R
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Re: 95 850 M56 Swap Write Up
'All my money is gone and I have an old Volvo.' - Bamse's Turbo Underpants
Current: 1995 Volvo 850 T-5R Manual - Bringing it back from the brink of death
Previous: 1996 Volvo 850 GLT - Totaled
Current: 1995 Volvo 850 T-5R Manual - Bringing it back from the brink of death
Previous: 1996 Volvo 850 GLT - Totaled
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- Posts: 2631
- Joined: Wed Apr 01, 2009 1:10 am
- Year and Model: 1995 Volvo 854 T-5R
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- Has thanked: 10 times
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I've had the T-5R off the road for about a week and a half while I've been adjusting a few things. I also took this opportunity to correct some of the things from when I did the swap. The reason my cooling fan was staying on continuously was because the ECT sensor connector was broken. I repaired the connector and I'm hoping that will fix both the cooling fan issue as well as the rough idle issue.
I also installed wiring for the reverse lights. The M56 I bought came with a VSS plug. That plug fits perfectly on the reverse light switch so I used that and lengthened the wiring enough to reach the transmission plug at the front of the car. I had an old PNP switch laying around so I stole two pins off of that and spliced them onto the end of the wiring so they can just be plugged right into the transmission plug.
I replaced my basic jumper wire (for pins 6 & 7) with a thicker wire that I also stole off of the old PNP switch. I crimped another pin onto the end of that wire and now the starter bypass wire can also plug right into the transmission plug. With some simple modifications I managed to use the old PNP plastic connector to keep my new wiring in place and make everything look fairly neat.
I'm installing an IPD HD TCV tomorrow and possibly adjusting the wastegate as well. Once that's done I can put everything back together and test out the new modifications. Hopefully it all works!
Edit: New wiring works perfectly!
I also installed wiring for the reverse lights. The M56 I bought came with a VSS plug. That plug fits perfectly on the reverse light switch so I used that and lengthened the wiring enough to reach the transmission plug at the front of the car. I had an old PNP switch laying around so I stole two pins off of that and spliced them onto the end of the wiring so they can just be plugged right into the transmission plug.
I replaced my basic jumper wire (for pins 6 & 7) with a thicker wire that I also stole off of the old PNP switch. I crimped another pin onto the end of that wire and now the starter bypass wire can also plug right into the transmission plug. With some simple modifications I managed to use the old PNP plastic connector to keep my new wiring in place and make everything look fairly neat.
I'm installing an IPD HD TCV tomorrow and possibly adjusting the wastegate as well. Once that's done I can put everything back together and test out the new modifications. Hopefully it all works!

Edit: New wiring works perfectly!
'All my money is gone and I have an old Volvo.' - Bamse's Turbo Underpants
Current: 1995 Volvo 850 T-5R Manual - Bringing it back from the brink of death
Previous: 1996 Volvo 850 GLT - Totaled
Current: 1995 Volvo 850 T-5R Manual - Bringing it back from the brink of death
Previous: 1996 Volvo 850 GLT - Totaled
- abscate
- MVS Moderator
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Bumped for link to Alex’s thread and VRD note too
ECM flashing service
viewtopic.php?f=6&t=91782
Polska, this is an excellent write up and we thank you again
ECM flashing service
viewtopic.php?f=6&t=91782
Polska, this is an excellent write up and we thank you again
Empty Nester
A Captain in a Sea of Estrogen
1999-V70-T5M56 2005-V70-M56 1999-S70 VW T4 BMW
Link to Maintenance record thread
Link To Volvo Glossary
A Captain in a Sea of Estrogen
1999-V70-T5M56 2005-V70-M56 1999-S70 VW T4 BMW
Link to Maintenance record thread
Link To Volvo Glossary
- Eddystone
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I found this very enjoyable and easy to read. Having done so, I will be taking the liberty of removing this task from my bucket list. 
Converted an different vehicle from auto to manual many years ago. Fun and satisfying, but I have learned to love my automatic.
This is a very nice write up and an excellent resource. Thank you for making the effort to document this process. I'll bet there are some readers here who don't know what it was like to do these things without the internet as a resource. Sometimes we had factory service manuals, but usually it was like inventing the wheel over and over.

Converted an different vehicle from auto to manual many years ago. Fun and satisfying, but I have learned to love my automatic.
This is a very nice write up and an excellent resource. Thank you for making the effort to document this process. I'll bet there are some readers here who don't know what it was like to do these things without the internet as a resource. Sometimes we had factory service manuals, but usually it was like inventing the wheel over and over.
1998 V70 Non-Turbo/Auto
1993 945 Turbo/Auto
1999 S70 T5 Turbo/Auto
All U.S. market models.
All on the road and running.
PM me if you are near Philadelphia.

1993 945 Turbo/Auto
1999 S70 T5 Turbo/Auto
All U.S. market models.
All on the road and running.
PM me if you are near Philadelphia.

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Hey, everybody, got a question: would the manual transmission from a 2.0L 850 watch the T3 engine from the C70(1)?
- amblerman
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Eddystone wrote: ↑Wed Mar 25, 2020 11:48 am I found this very enjoyable and easy to read. Having done so, I will be taking the liberty of removing this task from my bucket list.
Converted an different vehicle from auto to manual many years ago. Fun and satisfying, but I have learned to love my automatic.
What was the vehicle you did this on?
-A
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