PonchoCatalina
Registered Member
My '86 diesel burb has lost its cruise control and I haven't been able to solve the problem yet. For a while it worked intermittently, but now I've got nothing. I have read every cruise related thread on this site and have found some useful information (Dorian's assembly diagrams, the troubleshooting chart for checking voltage at the module connector, etc.). What I do know is that the stalk is good - I replaced it and have checked the module connector with a test light. The brake switch appears to be working - it turns off voltage to the connector when the brake is depressed, voltage resumes when brake is released. There is vacuum on the smaller of the two hoses connected to the servo. I'm running out of things to check.
Here are the things I would like to know: 1. how do I check the servo operation?; 2. how do I check the optical speed sensor operation?; 3. should there be vacuum on the larger vacuum hose that goes between the brake switch and the servo- if so, under what condition?; 4. how can I test the actual electronic circuit board cruise module?; and finally, is there a comprehensive troubleshooting guide/flowchart somewhere to systematically check all of the cruise components to determine where the problem is? If anyone can answer any of my questions it would be greatly appreciated - I'm going crazy trying to diagnose this problem. Thanks!
- Ian
Here are the things I would like to know: 1. how do I check the servo operation?; 2. how do I check the optical speed sensor operation?; 3. should there be vacuum on the larger vacuum hose that goes between the brake switch and the servo- if so, under what condition?; 4. how can I test the actual electronic circuit board cruise module?; and finally, is there a comprehensive troubleshooting guide/flowchart somewhere to systematically check all of the cruise components to determine where the problem is? If anyone can answer any of my questions it would be greatly appreciated - I'm going crazy trying to diagnose this problem. Thanks!
- Ian
