1997 850 fixing and resetting odometer

Post by **tryingbe** » 22 Jun 2014, 18:54

The odometer stopped at 228k for my 94 volvo for the longest time... car had 280k when I bought it. I changed the gear around 330k.

It's so easy to check.

https://www.matthewsvolvosite.com/forums ... php?t=6731

MilesCltrn · Post by **MilesCltrn** » 22 Jun 2014, 19:21

Just completed this repair on my '96 850 Wagon. (OBDII)

I found that attatching my 18mm socket [widest diameter at hand, but any would do] (a wrap of electrical tape around it for some grip) to my cordless drill, I was able to quickly advance the odometer by touching the spinning socket to the smooth edge of the edge of the gear from the front of the odometer display.

Would someone point me to the details of reading the OBDII computer for actual milage? (I've been w/o odometer for about 8 months, advanced 11k for approx.)

thedancingfiddle · Post by **thedancingfiddle** » 22 Jun 2014, 19:46

Check out this thread:
https://www.matthewsvolvosite.com/forums ... p?p=301702

and this site:
http://jonesrh.info/volvo850/index.html

I was finally able to read mine after a bunch of trial and error with a windows xp laptop and an ELM327 OBDII-USB interface. I used the Realterm program to issue the command line to the ELM327.

Good Luck!

Post by **JimBee** » 22 Jun 2014, 20:33

I read somewhere that pressing the reset while the car is moving can break the gear. I usually reset mine when I gas up, too, but only before I start up.

Post by **xHeart** » 22 Jun 2014, 20:38

JimBee wrote:I read somewhere that pressing the reset while the car is moving can break the gear.

true.

MilesCltrn · Post by **MilesCltrn** » 22 Jun 2014, 20:39

JimBee - rolling out of petrol station reset is what did mine in. IPD gear replacement went well. Old gear was missing one tooth and grimy yellow color.

thedancingfiddle · Post by **thedancingfiddle** » 23 Jun 2014, 05:13

Yes I've heard that resetting it while moving is not a good idea. You can bet I'll be extra careful once mine is working!

Post by **erikv11** » 23 Jun 2014, 09:47

And now for some odometer trivia: When you drive the car in reverse, the 850's odometer still counts upward!

thedancingfiddle · Post by **thedancingfiddle** » 23 Jun 2014, 19:23

So, I got it all back together, took it for a test drive, and nothing. Neither the odometer nor the trip meter are moving at all. At least all the dash lights work now...

Any ideas what could be the problem? I tested it with the new gear in by hand with an eraser, and it seemed to work smoothly then. The trip turned and the odo. turned at the right time and everything seemed good.

Could the little motor be bad? Has anyone heard of these failing?

thedancingfiddle · Post by **thedancingfiddle** » 24 Jun 2014, 12:27

Update: I got it working!

Took it all apart again, and checked that the pins were seated fully in the plug on the odometer module. They were. So I took the module out again, took the motor off and turned over the small gear. I had put it in there with the gear part in, towards the big gear, since this is how the old broken one was. But I guess the new one needs to be with the gear part outward, towards the motor? Doesn't really matter, since now it's working

Back together and test drove it and it is moving! Everything is turning at the correct time, though both trip and odometer are quite jerky and uneven in their movement. But I hear this is normal? On my old 850, the numbers turned very smoothly. But that car had a Yasaki cluster, so maybe that's why.

Anyway, thanks again to everyone on these forums - I could never have done this without all your comments and write-ups!

1997 850 fixing and resetting odometer

Re: 1997 850 fixing and resetting odometer