hey guys, I have a 97 volvo 850 with a 95 850 engine... I am having a problem with the speedometer not working after about 50 or so MPH... I have a blinking arrow that is On... and i read the code and it came up P0500 Vehicle Speed Sensor Malfunction A..... I just changed the speedsensor on the transmission.. and still the same thing... any ideas?

 

Which sensor did you change? The one on the top of the transmission or the one on the bottom down between the half shafts?

Is your ABS or Tracs light on?

...Lee

 

I changed the one on the bottom down between the half shafts, I didnt even know there was one on top, No abs light. The only light on, is the flashing Up arrow

 

The factory manual calls for Volvo measuring unit for proper testing, but it also stresses to inspect the connection(s) on the speed sensor(s).


JPN

[IMG]local://upfiles/6892/B027F52CB2B1475FA47EE04AFFC1FA10.jpg[/IMG]

 

You changed the right sensor. The one on the top of the transmission is the RPM sensor and they often get confused. Does your OBD-II code reader provide for a reset function? My son's cars has had the flashing arrow of death a couple of times and I hit the reset button and lifewas good for him again. Without resettingthe codesit stayed in a persistent fault mode.

Reset the codes and then check the connector and the wiring from the Vehicle Speed Sensor is my best advice.

...Lee

 

Which tranny do you have the 1997 or 1995?

 

I did reset the code, with my reader. It went off, and after driving for aminute, it the flashing arrow lights up again... I am using the 95 tranny.

 

I believe it is because you are using the 1995 tranny in the 1997 car. They are different.

 

how can I go about fixing this problem? I am using the 1995 wire harness... Do I have to rewire the speed sensor or what?

 

I think the problem is the 97 has one sensor and the 95 has 2 sensors.

 

https://volvoforums.com/m_79201/mpage_1/key_/tm.htm
Go through that post and others by him. Thats the post that had the same problem as you.

 

Im still not clear on what I need to do?

 

I know this relates to a post that is a bit old, but I noticed the reference to the ABS and Tracs lights....

• I'm driving a '98 S90 (US) -
• It threw a P0500 fault. The cluster went dead, except for the lights, flashing Mode Selector, Tracs Light...
• Volvo Dealer Service replaced the Vehicle Speed Sensor on the transmission, and cleared the code. 15 minutes down the road (they must not have test driven it), the cluster behavior returned.
• I took the car back to the shop.
• They wanted to replace the Instrument Cluster Wiring Plate.
• I ended up replacing the wiring plate myself.
• After replacing the wiring plate, I went to start the car, and it threw the P0500, again. (I never did clear it... I was figuring that disconnecting from the battery would take care of that)
• I'm thinking about clearing the code again, now that I have replaced the wiring plate, driving it, and seeing if the code returns.

Not sure where to look next.
I saw your question about the ABS light... What was that about?
Any insights would be helpful.

 

The ABS light would indicate you'd probably need to replace your ABS module, or get yours fixed.

Might want to pull the VSS that was installed in the trans and inspect it. I had one that was installed then about a day later my CEL went back on. There was a gear that was hitting the VSS in the trans and it chew the sensor up pretty good.

 

Thanks for the suggestions. Here's where I stand with this:

• I have not pulled the new VSS to see if it has gotten "chewed up" (what was your solution for that?)
• No ABS Light (I checked the bulb; it is fine.)
• I cleared the P0500 using OBDCOM Cable and Software; The code returns when starting the car. Is there some "trick" to reseting the code that I am missing?
  
• New development (I think): Turn Signals do not function. No indication of errors, like dash indicator light staying on or fast flashing for a bulb malfunction or missing.
  
• Possible significant detail: Shifter Assembly prevents shifting into Park. All other gears appear to be OK (other than this weird VSS related thing), PNP switch seems to be working (can only start the car in neutral)

Thoughts?

 

I wish I could add more useful tech to this because my 98 s70 just threw this code along with a P0733 gear 3 ratio incorrect code. I guess the main difference between our problems is everything on the dash works in my car but I have zero movement in any gear. I cleared the codes and was able to drive the car like normal about 2 or 3 hundred yards before it began again. I'm assuming since the codes were "reset" that it also reset the monitors which is why the CEL didn't immediately come back on like yours did. Did you ever get this resolved and what were the costs for the VSS? I also have a shifter situation where the car wont go immediately into park and the key wont come back out. I'm pretty sure that's just a little slop in the 12 year old cable and if I rock the car it engages fine. I hope you get your problems solved. I know how you feel I'm just beginning to troubleshoot mine. Good luck.

 

So this will not get rid of your P0500. but it will get your speedometer working, the VSS speed sensor leads need to get plugged into pins 5&6 on the smaller connector in the ecu box that leads to the cluster. If you dont have a VSS then you need to take from pins 5&6 on the ecu connector to the abs wheel sensor.