cruise control??

cbjones26 · Post by **cbjones26** » Thu May 15, 2008 8:05 am

ok the fuses are good, when i turn on the cc it shows up on the dash that its on but it doesn't engage if i set it at 60 mph an let off the gas the speed starts to drop .. any ideas?

aperson · Post by **aperson** » Thu May 15, 2008 11:49 am

Check the vacuum canister and cabling.

cbjones26 · Post by **cbjones26** » Thu May 15, 2008 2:13 pm

all the vacuum lines are hooked up. as far as i can tell the cable is good.!! is there a way to check to see if there is any vacuum ? the lines like i said are all hooked up but that doesnt mean anything!

neweywhat · Post by **neweywhat** » Wed Aug 20, 2008 1:24 am

I have been having what sounds to be the same issues. what i find is that if i set the cc and let off the gas the cc light will shut off and will not allow me to turn it back on until i bring the car to a full stop and shut the engine off. but once i do that i am right back to where i started. i have pulled the vacuum line off and i do have suction but im not sure if its enough to hold the throttle. i have also tested an do have my 12 VDC on the three positive wires going into my cc. (yes i know there is four but according to my schematics the black wire is ground and that is also good check.) i have also disconnected my throttle cable from the cc and test drove it. during that i found that the cc light will stay on until i make many actions such as accelerate and slow down or drop my speed below 10 MPH and then it shuts off and doesn't turn on again. much like before. im going to attempt to pick up a used CC from the junk yard and see if it will fix my problem but i am not getting my hopes up. i do believe that this does have to do the the vacuum not giving enough suction and being forced to work harder then it is designed to do in results to the CC turning its self off again. well if anyone wants to give a stab at this please let me know what you would do im banging my head agents the wall on this.

Post by **occasional demons** » Wed Aug 20, 2008 9:11 am

Get a hand vacuum pump w/gauge and see if the CC caniter itself does't have a bad diaphram. If it is leaking it won't matter how good the vacuum is at the line or if the electrical connections are correct. Autozone may have them to rent/buy. If anything it takes one more potential problem out of the equation.

neweywhat · Post by **neweywhat** » Wed Aug 20, 2008 12:24 pm

occasional demons wrote:Get a hand vacuum pump w/gauge and see if the CC caniter itself does't have a bad diaphram. If it is leaking it won't matter how good the vacuum is at the line or if the electrical connections are correct. Autozone may have them to rent/buy. If anything it takes one more potential problem out of the equation.

Thanks man ill try that let you guys know what i get.

asanti · Post by **asanti** » Wed Aug 20, 2008 5:40 pm

You may also want to check and make sure the wiring for the CC is intact. I blew my PS and ALT. belts on the highway last year and found that the belts had sheared through the CC wiring which is routed right above the alt. belt, on the pass side shock tower. It may not be your case but it doesn't hurt to check.

Later
Allex

neweywhat · Post by **neweywhat** » Wed Aug 20, 2008 10:21 pm

asanti wrote:You may also want to check and make sure the wiring for the CC is intact. I blew my PS and ALT. belts on the highway last year and found that the belts had sheared through the CC wiring which is routed right above the alt. belt, on the pass side shock tower. It may not be your case but it doesn't hurt to check.

Later
Allex

yeah I know they are good only because i have 13VDC on each wire except the black one while the car is in idle and the cc engaged and the black wire (ground) has good continuity with the chassy of the car. now i dont know what the voltage reading should be my schematics dont tell me all it says is what each wire is for and where its coming from.

Donkeypuncher · Post by **Donkeypuncher** » Wed Aug 20, 2008 11:18 pm

Your best bet is to check it with a DBRIII scan tool.

From the FSM:

A speed control malfunction may occur without a
diagnostic code being indicated. For further information information
and usage of the DRBIIIt scan tool and a more
complete list of Diagnostic Trouble Code and No
Trouble Codes, refer to the Powertrain Diagnostic
Manual.

If a road test verifies an inoperative system, and
the speedometer operates properly, check for:
² A Diagnostic Trouble Code (DTC). If a DTC
exists, conduct tests per the Powertrain Diagnostic
Procedures manual.
² A misadjusted brake (stop) lamp switch. This
could also cause an intermittent problem.
² Loose or corroded electrical connections at the
servo. Corrosion should be removed from electrical
terminals and a light coating of Mopar Multipurpose
Grease, or equivalent, applied.
² Leaking vacuum reservoir.
² Loose or leaking vacuum hoses or connections.
² Defective one-way vacuum check valve.
² Secure attachment at both ends of the speed
control servo cable.
² Smooth operation of throttle linkage and throttle
body air valve.
² Conduct electrical test at PCM.
² Failed speed control servo. Do the servo vacuum
test.

Maybe the servo is bad? I don't have cruise control so I can't really help much.

JerryR · Post by **JerryR** » Mon Nov 03, 2008 5:00 pm

neweywhat wrote:I have been having what sounds to be the same issues. what i find is that if i set the cc and let off the gas the cc light will shut off and will not allow me to turn it back on until i bring the car to a full stop and shut the engine off. but once i do that i am right back to where i started. i have pulled the vacuum line off and i do have suction but im not sure if its enough to hold the throttle. i have also tested an do have my 12 VDC on the three positive wires going into my cc. (yes i know there is four but according to my schematics the black wire is ground and that is also good check.) i have also disconnected my throttle cable from the cc and test drove it. during that i found that the cc light will stay on until i make many actions such as accelerate and slow down or drop my speed below 10 MPH and then it shuts off and doesn't turn on again. much like before. im going to attempt to pick up a used CC from the junk yard and see if it will fix my problem but i am not getting my hopes up. i do believe that this does have to do the the vacuum not giving enough suction and being forced to work harder then it is designed to do in results to the CC turning its self off again. well if anyone wants to give a stab at this please let me know what you would do im banging my head agents the wall on this.

i'm having exactly the same problem, but i'm building the cruisecontrol on my neon. the PCM has to send out e ground to the pins 1 and 2 of the servo. but mine doesn't do it

did you found a explanation?

greetings Jerry