I have been searching up and down, left and right trying to find this answer and am hoping to have someone shed some light on the topic. I’m having some issues with my cruise control with my 2003 Oldsmobile Alero.
Some background Information...
About a year ago I was driving on the highway with my cruise control set and maintaining my speed. I had a vehicle pull in front of me abruptly and I had to hit both my clutch and brake pedal fairly aggressively. After getting back up to speed less than a minute later I attempted to resume my set speed, and it didn’t work. Turned cruise off then back on, still wouldn’t set. It hasn’t worked since that day and I’m finally tired of it not working and am trying to diagnose the issue.
Unlike the cruise control issues that most Alero owners have with their on/off switch, mine seems fine. The button compresses fine and doesn’t pop back up, the light remains on showing that the cruise control is ON and staying ON.
I have checked all fuses, all are fine.
I have checked the clutch pedal switch and one wire has a good test for 12V and upon pressing on the pedal this is cleanly transferred to the second wire, this pedal switch seems good.
The Brake pedal switch is another story...it seems. The brake pedal has two switches going to it as seen in my attached image. The single switch with the brown and purple wires is like the clutch switch, one wire tested for a good 12V that is cleanly transferred to the other wire upon pressing the brake pedal. This is also the result for the second switch, black connector with the blue and orange wire only. Only difference is that the switch breaks the 12V circuit instead of completing in.
My issue is with the blue connector, the light green and green with white stripe wire. Neither of these wires have 12V power. Thinking that maybe they complete a grounded (negative) circuit, I tested both wires to ground. Neither of these wires is connected to ground either. So it would SEEM as though I have a broken wire on either one of these wires. I’m hoping someone can shed some light on what these wires are for, and where they lead so I can test them on the other end for continuity to check which wire is broken. Hopefully this is all the problem is.
To note, all testing on all wires and switches was completed with key out, key in, and key ON. Also with cruise OFF and cruise ON. This made no changes in my problem wires; the two greens.
Ive done some more digging, and it seems that this might be used for the TCC (Torque converter clutch) on automatic transmissions. Which would explain why the circuit is dead with my manual transmission on my Alero.
IF that is correct, it doesn't help explain why the cruise control wont "set".
If that's NOT correct, then it doesn't explain why the circuit is dead.