cruise control question
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On The Tree
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From: Orange County, Cali
cruise control question i bought the car with it never working. the fuse is also fine and intact. my question is, is there any way to tell if its just the module? if so, is it an easy swap? i saw one on ebay for an LT1, is it the same for an LS1?? some insight pls !! thanks guys!!
Joined: Nov 2003
Posts: 11,328
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From: Jacksonville, FL (originally from Toronto Canada)
Several easy things to check... Start off with the fuse. Did you test or replace the fuse (underhood fuse block) rather than just look at it? Countless times we've had people say a fuse was fine after visual inspection but it was actually blown. Always use a tester or replace with a known good fuse. Also, check the STOP/HAZARD fuse in the dash fuse panel. It powers the cruise control module as well although I'm sure you would have noticed that your brake lights weren't working.
On the M6 it's not uncommon for the cruise disengage switch on the clutch pedal bracket to get out of adjustment. It has a threaded mount that gets loose. If the switch doesn't close properly the cruise will never engage. There is a similar switch on the brake pedal but it seldom causes problems (doesn't hurt to check it anyway).
The next suspect would be the TS/multifunction switch. It's fairly easy to test. There is a small plastic cover below the turn signal lever on the column that you have to remove to access the switch connector. The connector has four wires - pink, gray, dark blue, and gray with black. The pink wire is the power supply from the fuse. The gray wire is the primary output - it should show power whenever the cruise switch is on. Dark blue is the "set" output - it should show power when the set button is pressed. Finally, gray with black is the resume/accelerate output - it should show power when the slide switch is pushed to the R/A postion.
There is very little that can go wrong with the cruise module itself and it is seldom the source of cruise control problems. I think you'll find the problem in one of the other things I mentioned.
On the M6 it's not uncommon for the cruise disengage switch on the clutch pedal bracket to get out of adjustment. It has a threaded mount that gets loose. If the switch doesn't close properly the cruise will never engage. There is a similar switch on the brake pedal but it seldom causes problems (doesn't hurt to check it anyway).
The next suspect would be the TS/multifunction switch. It's fairly easy to test. There is a small plastic cover below the turn signal lever on the column that you have to remove to access the switch connector. The connector has four wires - pink, gray, dark blue, and gray with black. The pink wire is the power supply from the fuse. The gray wire is the primary output - it should show power whenever the cruise switch is on. Dark blue is the "set" output - it should show power when the set button is pressed. Finally, gray with black is the resume/accelerate output - it should show power when the slide switch is pushed to the R/A postion.
There is very little that can go wrong with the cruise module itself and it is seldom the source of cruise control problems. I think you'll find the problem in one of the other things I mentioned.
Thread Starter
On The Tree
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From: Orange County, Cali
replaced the fuse... that wasnt the case.... so i move to the TS/ Malfunction switch... all lit up fine as you said when the appropriate buttons were pressed. removed the panels and checked the 2 threaded white colored mounts u mentioned for the brake and the clutch pedals... the clutch switch was actually loose and i tightened it closer so it closes all the way. i tightened the brake also just in case.
when i went for a test drive, it actually worked, but for literally 1 second. the manual says 40mph minimum for the CC to engage. so i tested it out about 4-5 times at various speeds above 40mph... i saw my spedo stay at those speeds right after i hit the set button for literally 1 second before starting to slow down again. also attempted the resume/accel switch w/no luck.
so with all those out of the question, could it be the module ??? anyone else have anything they can input?
when i went for a test drive, it actually worked, but for literally 1 second. the manual says 40mph minimum for the CC to engage. so i tested it out about 4-5 times at various speeds above 40mph... i saw my spedo stay at those speeds right after i hit the set button for literally 1 second before starting to slow down again. also attempted the resume/accel switch w/no luck.
so with all those out of the question, could it be the module ??? anyone else have anything they can input?
Joined: Nov 2003
Posts: 11,328
Likes: 345
From: Jacksonville, FL (originally from Toronto Canada)
Now that the switch position has been corrected, I would check that both the switches are actually working. You will find a black 2-pin inline connector under the dash near the steering column. It has a pink and a brown wire. Power is routed from the fuse through the pink wire to both the clutch and brake switches, returning to the cruise control module via the brown wire. Use a multimeter or test light to check for power on the brown wire. It should show 12V+ whenever the ignition is on regardless of the position of the cruise control switch. If not then either the clutch switch or the brake switch is faulty.
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On The Tree
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From: Orange County, Cali
i was finally able to get under the car again... have been busy since i last checked the last wires.... found the black 2 pin connector as you mentioned... my volt light tester lit up on both brown and pink wires... so it isnt a faulty brake or clutch switch as you mentioned. think this could be one of those rare occasions where it IS my module??
one last thing. i saw some engine bay's on the site a while back. i noticed that i only have one wire going to my throttle body lever and ive noticed some people have 1 or 2 wires going there... i know my car was in an accident before, could this be the reason why i dont have cruise control?
one last thing. i saw some engine bay's on the site a while back. i noticed that i only have one wire going to my throttle body lever and ive noticed some people have 1 or 2 wires going there... i know my car was in an accident before, could this be the reason why i dont have cruise control?
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Originally Posted by VtecDis
i saw some engine bay's on the site a while back. i noticed that i only have one wire going to my throttle body lever and ive noticed some people have 1 or 2 wires going there... i know my car was in an accident before, could this be the reason why i dont have cruise control?
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On The Tree
iTrader: (11)
Joined: Dec 2006
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From: Orange County, Cali
oh ok good. thats relieves me in a way... now i hope all the weeding out is done and i can take care of this once and for all.. i travel to Las Vegas alot and the CC would help greatly
Joined: Nov 2003
Posts: 11,328
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From: Jacksonville, FL (originally from Toronto Canada)
There are 35 diagnostic steps in the manual for a cruise control not functioning situation - only the last two deal with replacing the cruise module. That should give you an idea of how unlikely it is. It's not impossible and it may end up being the problem in this case but I would still check a few other things before spending the money on a new module.
Those signal wires you've tested so far all have direct runs to the cruise module. Before replacing it you should check that the signals you get inside the car are actually reaching the module. The module is mounted in the engine compartment on the left frame rail in front of the wheel opening. It has a 10-pin black connector. Check the following wires there using the same conditions as when checking them under the dash:
Gray - cruise on/off power from the switch
Dark Blue - power from the set/coast button
Gray with Black - power from the resume/accel slide switch
Brown - power from the brake and clutch switch
Black - ground
Pink - ignition power
The last four wires are data signals to the PCM and shouldn't be tested with a meter.
If the wires at the module all show the correct signals matching what you get under the dash then either the cruise module or the PCM is the likely problem. Hopefully it would be the cruise module because I'm sure you'd rather not replace your PCM.
Those signal wires you've tested so far all have direct runs to the cruise module. Before replacing it you should check that the signals you get inside the car are actually reaching the module. The module is mounted in the engine compartment on the left frame rail in front of the wheel opening. It has a 10-pin black connector. Check the following wires there using the same conditions as when checking them under the dash:
Gray - cruise on/off power from the switch
Dark Blue - power from the set/coast button
Gray with Black - power from the resume/accel slide switch
Brown - power from the brake and clutch switch
Black - ground
Pink - ignition power
The last four wires are data signals to the PCM and shouldn't be tested with a meter.
If the wires at the module all show the correct signals matching what you get under the dash then either the cruise module or the PCM is the likely problem. Hopefully it would be the cruise module because I'm sure you'd rather not replace your PCM.
