Cruise control was acting a might bit flaky and now is inoperable. On/Off switch on dash will illuminate amber, however the green “cruise” indicator on the tach will no longer illuminate.

The cable is attached and the unit appears to be connected properly, though a detached cable would not affect the dash light I imagine, I thought I’d mention this to rule it out.

Recent repairs fixed/replaced the brake switch that was causing a massive electrical drain, brake lights now illuminate correctly. Since the electrical drain is now corrected I assume it is not due to this switch, but just to be safe I will double check this today.

Next go to is the clutch switch. Unless I’ve read wrong, when this switch is bad it usually comes with a whole host of other gremlins (stalling, etc.) None of which are present, though I will also check this today. Is this the same switch that prevents the car starting unless the clutch is depressed or are there two switches to contend with? Would this switch cause the green “cruise” indicator to remain off?

If neither of these switches are the problem, what is the next logical step and how to go about it? I’ve been thumbing through the FSM without much luck.

 

On most cars there are two clutch switches. One at the top of the pedal and one towards the firewall. The top switch is a normally open switch that closes when the pedal contacts it and depresses the button if the clutch pedal is fully released. This would be the switch to investigate. The other clutch switch is for starting and is a normally open switch that is closed when the clutch is fully depressed.

For your new brake light switch. I'm not sure if this is applicable but did you get a new one from a touring? Are there non cruise and cruise model brake switch differences? If your on/off dash indicator is working then you're only culprit to chase down would be the circuit that needs to be closed for the cruise to engage.

 

I have seen the clutch switch (top of the pedal) cause cruise control problems. I would consider changing it... it's not expensive and if it doesn't go bad now it will go bad later.

 

There is an input from the brake switch to the cruise control. The brake switches are all the same I believe. I put cruise in my '94 R2 and just swapped in the actuator, brain, and buttons, that was it.

Go through the troubleshooting in the service manual and get your meter out.

Dale

 

I see now why I couldn’t find anything about the cruise control system in the FSM I have, I needed the Body Electrical Manual. Was thinking I was losing my mind there for awhile…

Anyway, I have used the self-diagnostics listed in the manual. Following the procedures, the flashing indicators noted that both the brake and clutch switch are functioning properly. Can I trust this or do I really need to get under there and test with a voltmeter? A back injury is currently making tight spots difficult. I was unable to run the diagnostic on the speed sensor just yet since it requires the car moving >25 mph and I just finished repainting the black trim pieces on the car.

I tested the actuator in the engine bay though I’m not entirely sure if the voltmeter I have is functioning properly, it’s exceedingly old. Also, I’m not 100% sure that I’ve tested the connections properly. It is a 4 prong plug that requires testing the ohm reading from prong A to C and B to D. Which side is up is a bit of a guessing game but it looks like the side with two.. uh.. slide guides I’m going to call them (keep the plug from going in at the wrong angle/upside down) is considered up as opposed to the sides with one guide. Either way, every connection combination I tried did not yield the proper ohms reading.

So, as it stands I’m going to be in need of a cruise control actuator in the engine bay. Anyone happen to know the going rate off the top of their heads or happen to have one they would be willing to part with?