On the way back from a recent long trip my conversion van had a problem. While driving down the freeway the cruise kicked off and the brake light and ABS light came on. I also noticed when I stopped that the speedo will not work below 25. In the past couple of weeks before the trip the CEL would come on for a short time and then go off. I tried to have the codes read but was told that they (Auto Zone) could not get a signal. Anyway is there anything that I can look for or try to fix this without spending a bundle just to get it diagnosed? I did try to disconnect the battery calbe for a minute or so but no change.

 

There is a wheel speed sensor on the back axle, it's likely that part went bad on you.

 

Thanks I will take a look and see what I find. I forgot to mention that it is a '99 B1500, I don't know if this makes any difference or not.

 

The red brake warning lamp and amber ABS warning lamp are located in the instrument cluster. The red brake warning lamp is used to alert the driver of a hydraulic fault or that the parking brake is applied. The red brake-warning lamp also is used to alert the driver of a problem with the RWAL system. The red brake-warning lamp illuminates when a message is sent over the bus to the cluster to illuminate the bulb. A ground is provided when:
- The parking brake is applied and the parking brake switch is actuated
- A hydraulic fault has occurred and the pressure differential switch is actuated
- A RWAL fault has occurred
The amber ABS warning lamp is used to alert the driver of an RWAL problem and identify DTCs stored in the CAB memory. If a system fault is detected during the self-test, or at any other time, the control module will illuminate the Antilock indicator lamp and store the fault code in the microprocessor memory. If a fault code is generated, the module will remember the code after the ignition is switched OFF. The microprocessor memory will store and display only one fault code at a time. The stored code can be displayed by grounding the RWAL diagnostic connector and counting the number of flashes on the indicator lamp. To clear the fault code, disconnect the control module connector or disconnect the battery for at least 5 seconds. During system retest, wait 30 seconds to make sure the fault code does not reappear.

(See attachment)

 

I would check the output shaft speed sensor on the trans.-The PCM compares this to the ABS sensors which could set an ABS fault code. I don't think the sensor in the rear end will cause the speedo to be inoperative.I'll double check the manual and repost what I find.