Tracs abs speedo issues

perhss70 · Post by **perhss70** » 03 Feb 2024, 13:49

Hello guys,
My 1997 S70 T5 has some issues regarding the abs that is not working and has the abs light on, the speedometer that sometimes doesnt display the speed and some times it does, and the tracs... I dont really know what is wrong with it and im not sure how its supposed to work but when i press the tracs button the tracs off light appears and when i let the button the light dissapears. If im correct the issues are related to each other. My main issue is the speedometer and i was wondering if anybody has encountered something similar.
Cheers.

Post by **misha** » 03 Feb 2024, 15:47

Speedometer signal goes through abs/tracs module.
You have a bad abs sensor(s),their wiring or bad abs/tracs module...VOL-FCR or dealership is needed to read the codes.
TRACS is always ON by default.
You can turn it off by pressing the switch and TRACS OFF will illuminate on the cluster.

Usually...when something is wrong with the abs system...abs/tracs light is on.
If abs is not working...traction control will also not work.
viewtopic.php?p=46827

perhss70 · Post by **perhss70** » 04 Feb 2024, 02:41

misha wrote: ↑03 Feb 2024, 15:47 Speedometer signal goes through abs/tracs module.
You have a bad abs sensor(s),their wiring or bad abs/tracs module...VOL-FCR or dealership is needed to read the codes.
TRACS is always ON by default.
You can turn it off by pressing the switch and TRACS OFF will illuminate on the cluster.

Usually...when something is wrong with the abs system...abs/tracs light is on.
If abs is not working...traction control will also not work.
viewtopic.php?p=46827

Thanks for the reply.
I would love to download vol fcr because it would be nice to have. I looked around and cant find a crack. Do you know where i can find the program? Also i saw some people talking about an 850 OBD II app on android. Would it work on my car? Do the two of them have any significant differences?
Thanks in advance

Post by **misha** » 04 Feb 2024, 06:05

850 OBDII app will work but with specific obdII adapter.
I never used it but here on MVS are plenty members that knows how to use it.

I'm affraid that your abs module might be replaced somewhere in the past since it always turn on both abs & tracs light.
As far as i understand...you have just Abs light on.
Tracs is fitted only on automatic transmission cars.
Is your car automatic?

perhss70 · Post by **perhss70** » 04 Feb 2024, 06:51

misha wrote: ↑04 Feb 2024, 06:05 I'm affraid that your abs module might be replaced somewhere in the past since it always turn on both abs & tracs light.
As far as i understand...you have just Abs light on.
Tracs is fitted only on automatic transmission cars.
Is your car automatic?

That makes a lot of sense.
ABS light permanently on. Tracs light on only when i press the button. My car is a manual.
My dad had changed the dashboard in the past. Maybe he just added the tracs switch by mistake then?

Post by **foggydogg** » 04 Feb 2024, 08:43

perhss70 wrote: ↑04 Feb 2024, 06:51
That makes a lot of sense.
ABS light permanently on. Tracs light on only when i press the button. My car is a manual.
My dad had changed the dashboard in the past. Maybe he just added the tracs switch by mistake then?

The ABS module in our cars has a known issue with cold solder joints on the circuit board. Since he speedometer signal goes through that system as noted, that could be the root cause here. While randomly changing parts is not a good diagnostic habit, if the car has the original module it is long overdue for repair anyway. There are several vendors in the States - Midwest ABS is one - but I don't know about Europe.

perhss70 · Post by **perhss70** » 04 Feb 2024, 08:59

foggydogg wrote: ↑04 Feb 2024, 08:43
perhss70 wrote: ↑04 Feb 2024, 06:51
That makes a lot of sense.
ABS light permanently on. Tracs light on only when i press the button. My car is a manual.
My dad had changed the dashboard in the past. Maybe he just added the tracs switch by mistake then?
The ABS module in our cars has a known issue with cold solder joints on the circuit board. Since he speedometer signal goes through that system as noted, that could be the root cause here. While randomly changing parts is not a good diagnostic habit, if the car has the original module it is long overdue for repair anyway. There are several vendors in the States - Midwest ABS is one - but I don't know about Europe.

Lucky for me i study electical engineering and i know soldering. Also it happens that my dad has a car part store with used volvo-saab parts
should i resolder the module or just replace it. Replacing is easier but maybe the replacement unit does the same?

perhss70 · Post by **perhss70** » 04 Feb 2024, 09:03

https://www.amazon.de/-/en/7170/dp/B00E ... 143&sr=8-1 should this work with vol fcr?

Post by **foggydogg** » 04 Feb 2024, 09:27

It would only take a few minutes to swap it; there is an outside chance the spare will be fine for diagnostics. Get a fresh, quality torx bit, use some patience. If the car is a keeper, the prudent thing would be to cure it. There are online tutorials for the repair but homegrown fixes seem to be hit-or-miss. Getting the module open is the first challenge; getting it sealed back up is the last.
One troubleshooting technique is to unplug/plug-in the cables just in case some corrosion had infected the pins, but that is a low percentage possibility.
Some more info here
https://midwest-abs.com/

Post by **misha** » 04 Feb 2024, 10:09

perhss70 wrote: ↑04 Feb 2024, 09:03 https://www.amazon.de/-/en/7170/dp/B00E ... 143&sr=8-1 should this work with vol fcr?

That might be the problem since Vol-FCR works only with serial (db9) cable and laptop or desktop with serial port and on COM1port ONLY.

There are members on volvospeed.com who managed to make it work with usb cable.