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cruise control won't engage 96, also a mystery connector?
Vehicle: 1996/automatic/coupe/with auto climate control
Trying to repair my cruise control, which stopped working. CC doesn’t engage at all. CC Symptoms:
-CC was working fine for years up until few days ago
-Few days ago, I fixed my HVAC vacuum problem (I had accidentally pinched the source vacuum line behind the passenger hush panel, by getting the line caught in the nearby relay box cover – fixed though, and HVAC works well now).
-while repairing my HVAC, I was fiddling a lot with the HVAC programmer under the driver hush panel, perhaps I knocked something loose? but everything there looks ok
-with the engine running, I’ve checked for vacuum at the 3-way check valve under the passenger fuel rail cover – OK
-“ “ I’ve checked for vacuum coming from the vacuum ball tank – OK
-“ “ I’ve checked for vacuum going to the servo – OK
-Cruise fuse – OK
-HVAC works well (as these 2 systems rely on the same vacuum source)
-I tried to find the diagnostic procedure in the FSM for cruise control, but each section I went to referred me to the other, like monkey-in-the-middle
Also, I noticed that the brake light/cruise vacuum switch (the switch labeled “10211657 5289” that has the thick rubber vacuum hose routing out through the firewall to the cruise servo) has an empty 2-pin plug/socket, but no nearby connectors for it. Odd.
**Possibly related……..Does anyone know what this 4-pin connector is for? It branches off the main/thick harness of the steering column, and has the following wires (I spent 2 hours thumbing through my FSM trying to identify it, couldn’t). I can’t figure out where it gets plugged into, if at all.
-pink -gray -gray w/ black stripe -purple
I’ve tried searching CF and other forums, and found a few related threads:
Look for maybe C235 in your wiring diagrams - that's maybe a jumper to the Cruise Module Connector harness.
8A-202-27 for the connector and in the wiring diagrams for the cruise control I'd think you can ID it. I didn't try to ID the wire colors maybe a snapshot of the end of the connector that isn't connected would help.
In your second pic with the green circle, that is the connection for the cruise control stalk (switches) on the steering column. The mating connector has a "circuit board" like connector, and the wire is about a 3/16" diameter black-sheathed cable. It comes out of the base of the steering column with the other wires and cables. Find, and re-connect the stalk, and the cruise should work.
EDIT: I see the other end of the stalk wiring. In the second pic, there are 4 wires on the left of the bundle coming out of the column. Pink, grey, blue, and black. They are above the big grey connector, and appear to be tucked between the big pink and big red wires. . I can just see the edge of the "circuit board connector". (I guess Corvette didn't use the black sheathed wire like other carlines did).
In the first pic, you circled the electrical connection for the vacuum switch. In a manual trans car, this would be on the clutch pedal. I do not know offhand whether the C4 uses this connection or not on automatics. suspect not. In other GM carlines of the era, the connector would contain (2) grey wires. Look in the vicinity for an orphan connector with 2 greys, and if you find one, plug it in. If you can't, reconnect the stalk as above and try it. If it still doesn't work, we'll go from there. Happy hunting.
thanks! Problem solved. My issue was that I was unable to find the circuit-board like cruise control connector as it was buried in the main steering column harness. Found it, and plugged it into the “mystery connector “
Hello,
I have the same issue. In my 1993 ZF6 C4 the cruise control does not work. So this connector makred in blue have to be plugged in order to CC works? Or is ok now?
I mentioned that I believe you're fine. Do the balance of the diagnostics if you have a cruise issue.
There's all of the diagnostics required I believe if you use 8A-34-0 and the pages that follow in Book 2 of the FSM.
If the WaterMarks ever become an issue for you drop me an email and I believe we can fix that. Mine have no WaterMarks and I've modified some of the restrictions.
Yes, but now I'm looking on the page 5-7 in the book 1 and there is shown a plug which matches this connector marked in blue, but I can not find anywhere what is the function of this plug.
Now I'm a bit confused.
Section 9B Cruise Control does not address this issue.
Thank you, now it is clear / explained to me.
So it seems to be ok, time to look for other causes of not working cruise control in my C4.
I have a 96 LT4 Vert and my cruise sometimes doesn’t want to engage and I will pull out on my clutch pedal with my foot and it will work. The switch on the clutch pedal needs to be adjusted.
Small update,
I have fixed the cruise control in my C4.
So I can confirm that in C4 with manual transmission the connector I marked in blue should remain unplugged. All were ok with them.
1) I had to adjust the switch on the brake pedal where the dump hose comes in, because the notch did not hide (as it is shown in the FSM few posts above) when the pedal was not pressed, so the hose was constantly open and did not hold the vacuum. I also readjusted the other switches but I think the remaining two (one the brake pedal, one on the clutch pedal could already work fine)
2) The check valve near the fuel rail had few holes, so it did not hold the vacuum (even when I pumped it). Despite of this the air condition, heating and ventilation (HVAC) worked fine in my C4. Because I'm from Poland and I would have to wait for a brand new valve a few weeks I just clogged the holes with a gel glue and rolled the check valve with a tape. I could pump the pressure but it did not hold the pressure - it was gradually decreasing - despite of this I put it on the car but at that time nothing changed, the cruise control did not work
3) Last thing I had done before the cruise control started working and might have helped was unplugging and reconnecting the cruise control relay (it looked like brand new, also inside when I removed the plasic case) which is located near the steering column) - I took the car for a drive and the cruise control surprisingly started working
So in the result the cruise control is working fine now (all the features) in my C4.
I hope this photos will be useful for someone who will attempt to fix the cruise control in his C4.
Vehicle: 1996/automatic/coupe/with auto climate control
Trying to repair my cruise control, which stopped working. CC doesn’t engage at all. CC Symptoms:
-CC was working fine for years up until few days ago
-Few days ago, I fixed my HVAC vacuum problem (I had accidentally pinched the source vacuum line behind the passenger hush panel, by getting the line caught in the nearby relay box cover – fixed though, and HVAC works well now).
-while repairing my HVAC, I was fiddling a lot with the HVAC programmer under the driver hush panel, perhaps I knocked something loose? but everything there looks ok
-with the engine running, I’ve checked for vacuum at the 3-way check valve under the passenger fuel rail cover – OK
-“ “ I’ve checked for vacuum coming from the vacuum ball tank – OK
-“ “ I’ve checked for vacuum going to the servo – OK
-Cruise fuse – OK
-HVAC works well (as these 2 systems rely on the same vacuum source)
-I tried to find the diagnostic procedure in the FSM for cruise control, but each section I went to referred me to the other, like monkey-in-the-middle
Also, I noticed that the brake light/cruise vacuum switch (the switch labeled “10211657 5289” that has the thick rubber vacuum hose routing out through the firewall to the cruise servo) has an empty 2-pin plug/socket, but no nearby connectors for it. Odd.
**Possibly related……..Does anyone know what this 4-pin connector is for? It branches off the main/thick harness of the steering column, and has the following wires (I spent 2 hours thumbing through my FSM trying to identify it, couldn’t). I can’t figure out where it gets plugged into, if at all.
-pink -gray -gray w/ black stripe -purple
I’ve tried searching CF and other forums, and found a few related threads:
I, too, have a 96 with a manual trans with a cruise control that is not working. During my debugging, I am focused on the Cruise control dump relay and found it on the bracket by the steering column right next to the flasher. It looks suspicious in that the cover is corroded with white powder so I want to inspect it further. I can use some help removing it from it's bracket. Does anyone know the trick to sliding it off the bracket?
09-18-2018, 10:38 AM
cruise control won't engage 96, also a mystery connector?
