OK,

Since I have typed this twice its brief. I am not responsible if you muck up your car. This is what I did and what you do to your car is your own business. I am just a garage DIYer.

To use the onboard ABS diagnostic on 2001 (not sure what all years it applies to):

• Drive vehicle over 20 MPH for at least one minute
• Turn ignition OFF.
• Ground Terminal NINE (9). I used the body terminal FOUR (4).

Codes:

• 12 = Start of message strings. A maximum of three codes will appear in the order of the latest one first to the oldest and then back to 12.
• 21 = Front RIGHT sensor (OPEN circuit)
• 22 = Front RIGHT sensor (SHORT circuit)
• 25 = Front LEFT sensor (OPEN circuit)
• 26 = Front LEFT sensor (SHORT circuit)
• 31 = Rear RIGHT sensor (OPEN circuit)
• 32 = Rear RIGHT sensor (SHORT circuit)
• 35 = Rear LEFT sensor (OPEN circuit)
• 36 = Rear LEFTsensor (SHORT circuit)
• 41 = Actuator Front RIGHT outlet soleniod valve
• 42 = Actuator Front RIGHT inlet soleniod valve
• 45 = Actuator Front LEFToutlet soleniod valve
• 46 = Actuator Front LEFT inlet soleniod valve
• 51 = Actuator Rear RIGHT outlet soleniod valve
• 52 = Actuator Rear RIGHT inlet soleniod valve
• 55 = Actuator Rear LEFT outlet soleniod valve
• 56 = Actuator Rear LEFT inlet soleniod valve
• 57 = Power supply (low voltage)
• 61 = Actuator motor or motor relay
• 63 = Solenoid valve relay
• 71 = Control unit.

If querying the ABS computer you get

• ABS Warning lamp stay on when ignition switch is turned on.
  • Control unit power supply circuit
  • Warning lamp bulb circuit
  • Control unit or control unit connection
  • Soleniod valve relay stuck
  • Power supply for solenoid valve relay coil
• ABS warning lamp stays on, during self diagnosis.
  • Control unit
• ABS warning lamp does not come on when ignition switch is turned on
  • Fuse, warning lamp bulb or warning lamp circuit
  • Control unit
• ABS warning lamp does not come on during self diagnosis.
  • Control unit

If you are suspecting a sensor and its confirmed by the codes above, you can get an OHm meter and check the sensor. Apply the lead to the sensor and if you are between .8 and 1.85 KOHms, the sensor is ok, your problem is elsewhere.

That should help people figure out where to start with these ridiculously expensive sensors!

Good luck!

 

I finished my rear sensor and it was much easier than a front sensor. I tried it the "old" way by twisting and trying to pry it of. No go as I broke the sensor and most of it was still in the mounting plate.

Save some time. Pull the rotor and caliper assembly and you can just hammer it out and save time. I sanded the rust out of the hole and found a piece of wood so I could use a dead blow hammer to install the new one.

Be VERY careful as to have the screw hole lined up before you drive the sensor in to far as it will be difficult to change its position without breaking it. I seated the sensor by hand and put the screw in and got a few turns in it. A gave a couple whacks with the hammer and then followed with tightening the screw. I repeated this procedure until it was tight.

My new sensor tested at 1.1 KOHms when I bought it and it cleared the light and the codes in the computer. No reseting necessary.

 

Good informative post. There seems to be some debate however whether or not to use pin 9 or pin 8 to ground.

 

This should help

 

good info

so far I've been lucky and the OEM sensors haven't given me any trouble. I had an ABS issue with intermittent pressure loss but a good brake flush took care of that 8 or 9 years ago with no issue since.