How JustAnswer Works:
  • Ask an Expert
    Experts are full of valuable knowledge and are ready to help with any question. Credentials confirmed by a Fortune 500 verification firm.
  • Get a Professional Answer
    Via email, text message, or notification as you wait on our site.
    Ask follow up questions if you need to.
  • 100% Satisfaction Guarantee
    Rate the answer you receive.
Ask George H. Your Own Question
George H.
George H., Subaru Certified Technician
Category: Subaru
Satisfied Customers: 18529
Experience:  ASE Master Tech 15 + Years
13574682
Type Your Subaru Question Here...
George H. is online now
A new question is answered every 9 seconds

Subaru B9 Tribeca i have a vechicle speed sensor fault po

Customer Question

i have a vechicle speed sensor fault po 500 on a subaru tribeca 2007. i changed the sensor and it the code comes right back. websites that i read say the wheel sensors are part of that circuit causing the code. how do i test the four wheel sensors so i dont have to buy them all
Submitted: 5 years ago.
Category: Subaru
Expert:  George H. replied 5 years ago.

Hello I will help you with your question,

 

The P0500 code is either of the front wheel speed sensors so having a scantool that can see the sensor input allows you to see which sensor is reporting incorrect information and you can see if it is the sensor, the tone ring or the wiring is the problem

 

The diag for the code is below

 

Click here

 

 

Look this over and let me know what further questions you have about this

 

Thank you

 

 

Customer: replied 5 years ago.
i have a obd 2 code reader only the book that came with it had me change the vechicle speed sensor which was a 4 hour job. how can i test the wheel sensors with out any scaning tools. and why do you think its front and not rear ???
Expert:  George H. replied 5 years ago.

Unless you have an oscilloscope or a very good multimeter you cannot test the sensors. Or you need a scantool that can communicate with the ABS system in this vehicle.

 

If you read the diagnosis procedure you will see that only the front sensors are used in the criteria to have this code set. The are the only sensors that provide data to have the code set.

 

Let me know how I can help you

 

Thanks

 

 

Customer: replied 5 years ago.
i just called my parts guy the front wheel sensor are in stock for 42 dollars each im thinking ill just take a shot and change both . from the way im understanding then theres no way its the rear sensors. just for my knowledge why would the fan run continuously as well as the 4 dash lights
Expert:  George H. replied 5 years ago.

It is not the rears, be sure to take a look at the wiring as well as the sensors and any rust/corrosion on the tone ring and the sensor mounting.

 

Usually there will be a fail safe mode if you have warning lights and cooling fan running at all times.

 

The P0500 is the only code you pulled?

 

 

Customer: replied 5 years ago.
it was and still is the only code that i pull out even after erasing it or disconnecting battery it come back on in a second the dealer said theres also abs rings how do i check them
Expert:  George H. replied 5 years ago.

The ABS rings are the tone rings that have ridges the sensors read. If the code resets right away it is not the tone rings.

 

I need to know a lot more about what has been done and what you are seeing that the warning lights are on (4 which ones?) and the cooling fan runs continuously.

 

You should hold off on replacing anything until you find out why this is happening as the P0500 may be a false code.

 

 

Customer: replied 5 years ago.
i should tell you that this happens while the car is parked and running the cruise light, the abs light , the check engine light and vechile control/sway light are on. the cooling fans runs continuously when code comes on. i changed the vechicle speed sensor to transmission like the code read. it was a tough job, very tight are to work in .
Expert:  George H. replied 5 years ago.

OK part of the code set criteria is to turn the fan on at 50% speed and you would have the Traction control, ABS, MIL and the cruise as a result of the P0500. Go ahead and replace the sensors, you can try one at a time as you have a shorted sensor and maybe you will get lucky the first time. I'm not sure where you got the information to replace the speed sensor in the transmission but that was incorrect

 

Let em know what I can do to help

 

Thank you

 

 

Customer: replied 5 years ago.
i will give it a shot in the am thanks
Expert:  George H. replied 5 years ago.

OK let me know how I can help

 

Thanks

 

 

Customer: replied 5 years ago.
i changed the front wheel sensors the codes cleared within ten minutes of driving a po700 and all the same warning lights came back on
Expert:  George H. replied 5 years ago.

The P0700 is a code that directs you to pull the codes from the transmission. Can you get the code from the trans?

 

You no longer have the P0500 that you replaced the sensors for?

 

 

Customer: replied 5 years ago.
the po500 is cleared the car went back to normal for ten minutes driving time. then the lights came back with a po700 code
Expert:  George H. replied 5 years ago.

OK the P0700 is a notice to the PCM to turn on the warning light and that there is a code stored in the transmission so you need to pull the transmission codes.

 

 

Customer: replied 5 years ago.
can i check them with my obd2 scanner
Expert:  George H. replied 5 years ago.
No you will need a scanner that can communicate with the transmission computer in the Van
Customer: replied 5 years ago.
ill go buy a scanner what do i call it
Expert:  George H. replied 5 years ago.

There are many types of scanners and any that can communicate with the transmission computer will be several thousand dollars. The Subaru scantool which has full communication with the systems in this vehicle is the Subaru Select Monitor.

 

Some of the SnapOn products and the OTC products can communicate as well.

 

 

Customer: replied 5 years ago.
George all worked out well i put the original transmission harness back in and that cleared the po700 codes which leads me to believe the new one was defective
Expert:  George H. replied 5 years ago.
I was unaware that you had the transmission harness out, I thought you changed the wheel and speed sensors?