Hello all,

I suddenly developed a problem with my '99 Ford Ranger. Yesterday while backing out of the driveway the ABS light came on
and then the O/D light began flashing. I depressed the O/D button on the gearshift handle but the light would not go out. After driving for a 3 minutes I noticed that the truck was having problems accelerating and it kept shifting gears rather violently. I then noticed that the speedometer was not working. All of this happened out of the blue with no warning. I have never seen this kind of behavior out of this truck. Does anyone have any ideas about what this could be? I checked the transmission fluid, no problem there. So I'm wondering if this could be a transmission problem or a problem with the computer. Thanks.

ray

 

I think you might have to have the codes pulled to find out what kind of problem you have. Normally your anti-lock brake control module will store a code when the ABS system is messing up.

My guess (and it is only a guess) is that your rear anti-lock brake sensor (mounted in the rear differential case) might be the problem. That is the sensor that controls your ABS system and also provides vehicle speed data to the PCM.

My Ford Manual actually has a test procedure for the ABS sensor:

Component Test

Sensor — Rear Anti-Lock Brake

1. Disconnect the rear anti-lock brake sensor;

2. Measure the resistance between rear anti-lock brake sensor terminals. If the resistance value is between 800 and 3500 ohms, go to Step 3. If the resistance value is not between 800 and 3500 ohms, replace the rear anti-lock brake sensor*;

3. Measure the resistance between one of the rear anti-lock brake sensor terminals, and ground. If the resistance is greater than 10,000 ohms, go to Step 4. If the resistance is lower than 10,000 ohms, replace the rear anti-lock brake sensor*;

4. Measure the AC voltage between the rear anti-lock brake sensor, while rotating the rear wheel at approximately 8 km/h (5 mph). If the AC voltage is approximately 650 mV RMS, the rear anti-lock brake sensor is OK. If the AC voltage is not approximately 650 mV RMS, replace the rear anti-lock brake sensor*;

*ABS Sensor Removal and Installation

1. Raise and support vehicle.

Note: Clean off dirt and debris that may have collected around the rear anti-lock brake sensor before removal.

2. Disconnect the rear anti-lock brake sensor electrical connector.

3. Remove the bolt.

4. Remove the rear anti-lock brake sensor.

Note: Thoroughly clean the mounting surface.

Note: Inspect the anti-lock brake sensor O-ring for damage; lightly lubricate the O-ring with SAE-75W-140 High Performance Rear Axle Lubricant F1TZ-19580-B or equivalent meeting Ford specification WSL-M2C192-A.

5. To install, reverse the removal procedure.

Hope this helps!

 

I HAD THE SAME PROBLEM AND ALL I HAD TO DO WAS REPLACE THE REAR DIFF ABS SENSOR AND ALL PROBLEMS WERE RESOLVED.

 

Thanks Rockledge and James. This makes me feel a lot better. I'll have the codes pulled tomorrow.

ray

 

you can have the codes pulled on an OBD2 scaner and it will show no codes or you can find the orange/black wire above the emergency brake and ground it and have the ABS light flash you a code

 

The org/blk wire is only for RABS, ABS requires a scanner.