Speedo acting funny after swap. Volvo 850 '92 GLT

Post by **koralski** » 28 Mar 2025, 15:46

I replaced my original 1992 speedo with a V70 P80 speedo with the digital kilometer readout. Now its acting funny, not showing the correct speed etc; does this dash pull the speed from the gearbox or from the ABS sensors?

I did not have this issue with the previous dash.

Thanks in advance!

Post by **misha** » 28 Mar 2025, 16:15

1997 & 1998 s,v,c or xc70 instrument clusters are not interchangeable with pre '96 850.

It will work ONLY on '96 & '97 850 which originally had VDO clusters.

Also...'99 & '00 s,v,c or xc70 instrument cluster will not work in any 850 nor pre '99 70 series cars because of CAN protocol introduced.

Post by **koralski** » 28 Mar 2025, 16:48

It works, i had a VDO cluster.

Do you mean that it will not work fully, and this might be what is causing the issue?

Post by **koralski** » 28 Mar 2025, 16:51

Is there even another option? All clusters i see for a '94 are VDO.

Post by **misha** » 28 Mar 2025, 17:01

Speedometer on pre '96 cars takes analog output from speed sensor on gearbox.

'96 and later cars speedometer takes digital output from abs/tracs module.

I guess that you could tap into front wheel abs sensors but i can't verify that signal would be correct.
And you will need pre '99 cluster ONLY from 70 series p80.

Post by **misha** » 28 Mar 2025, 17:43

koralski wrote: ↑28 Mar 2025, 16:51 Is there even another option? All clusters i see for a '94 are VDO.

There is Yazaki cluster for 850,looks similiar to 70 series cars cluster but it is not interchangeable with VDO and they are pretty rare...at least on B5254S cars:

Post by **scot850** » 28 Mar 2025, 19:17

99- clusters are not interchangeable with other cars at all. The are loaded with the Vin#. They cannot be re-programmed according to Volvo (unless someone knows how). They are supposedly a one shot program circuit board. It may be able to work assuming the same transmission is fitted, but you cannot talk to the ECU/TCU unless the Vin#'s match in both.

Neil.

Post by **koralski** » 29 Mar 2025, 02:45

misha wrote: ↑28 Mar 2025, 17:43
koralski wrote: ↑28 Mar 2025, 16:51 Is there even another option? All clusters i see for a '94 are VDO.
There is Yazaki cluster for 850,looks similiar to 70 series cars cluster but it is not interchangeable with VDO and they are pretty rare...at least on B5254S cars:
Screenshot_2025-03-29-00-43-04-960.jpg

No, my car doesn't have this cluster. I am going to splice the wires and fingers crossed it will work!

By the way, do you know if holding the hour and minute button changes from MPG to L/100km?

Post by **misha** » 29 Mar 2025, 02:52

Never tried...but it should work.

Post by **koralski** » 29 Mar 2025, 03:11

misha wrote: ↑29 Mar 2025, 02:52 Never tried...but it should work.

Do you know how should I splice the cables? Which to where etc?