Cruise cntrl works a min then quits
 

I just got an 04 dodge I'm findin lil odds and ends wrong with it.. Nothin to bad except for the cruise control.. I assume the high idle is enabeled because when stopped I can turn cruise on and idle up to 1500 RPM's.. But whenever I get on the interstate and try to set the cruise it will engage and hold it at 70 just like it is supposed to do.. But only for about 6-60 seconds... Then it will shut off just like you turned it off.. And after it kicks off the first time it will not even try to engage again untill the key is shut off and restarted.. It will however high idle up to 1500 RPM's any time... Before or after the cruise has been on and kicked off... Does anyone know what may be causing this, and how to fix it.. I've just had it over the weekend so if it's something big I'm gonna takeit back to see if they'll fix it... Although I'd alot rather do it myself than take it to the dealership...

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bump Any body got any ideas?

Lemme look something up here, be a minute.

5.7L Gas / 5.9L Diesel
The speed control system is fully electronically controlled by the Powertrain Control Module (PCM). If equipped with
a diesel engine, electronic control of the speed control system is integrated into the Engine Control Module (ECM).
A cable and a vacuum controlled servo are not used. This is a servo-less system. The controls consist of two
steering wheel mounted switches. The switches are labeled: ON/OFF, RES/ACCEL, SET, COAST, and CANCEL.
The system is designed to operate at speeds above 30 mph (50 km/h).

OPERATION
When speed control is selected by depressing the ON switch, the PCM (the ECM with a diesel engine) allows a set
speed to be stored in its RAM for speed control. To store a set speed, depress the SET switch while the vehicle is
moving at a speed between 35 and 85 mph (56.2 and 136.8 kph). In order for the speed control to engage, the
brakes cannot be applied, nor can the gear selector be indicating the transmission is in Park or Neutral.
The speed control can be disengaged manually by:
² Stepping on the brake pedal
² Depressing the OFF switch
² Depressing the CANCEL switch.
² Depressing the clutch pedal (if equipped).
NOTE: Depressing the OFF switch or turning off the ignition switch will erase the set speed stored in the
PCM (the ECM with a diesel engine).
For added safety, the speed control system is programmed to disengage for any of the following conditions:
² An indication of Park or Neutral
² A rapid increase rpm (indicates that the clutch has been disengaged)
² Excessive engine rpm (indicates that the transmission may be in a low gear)
² The speed signal increases at a rate of 10 mph (16kph) per second (indicates that the coefficient of friction
between the road surface and tires is extremely low)
² The speed signal decreases at a rate of 10 mph (16kph) per second (indicates that the vehicle may have
decelerated at an extremely high rate)
Once the speed control has been disengaged, depressing the RES/ACCEL switch (when speed is greater than 30
mph or 48.2kph) restores the vehicle to the target speed that was stored in the PCM (the ECM with a diesel
engine).
While the speed control is engaged, the driver can increase the vehicle speed by depressing the RES/ACCEL
switch. The new target speed is stored in the PCM (the ECM with a diesel engine) when the RES/ACCEL is
released. The PCM (the ECM with a diesel engine) also has a 9tap-up9 feature in which vehicle speed increases at
a rate of approximately 2 mph (3.2kph) for each momentary switch activation of the RES/ACCEL switch.



DIAGNOSIS AND TESTING - ROAD TEST
Perform a vehicle road test to verify reports of speed control system malfunction. The road test should include attention
to the speedometer. Speedometer operation should be smooth and without flutter at all speeds.
Flutter in the speedometer indicates a problem which might cause surging in the speed control system. The cause
of any speedometer problems should be corrected before proceeding. Refer to Instrument Cluster for speedometer
diagnosis.
If a road test verifies a system problem and the speedometer operates properly, check for:
² A Diagnostic Trouble Code (DTC). If a DTC exists, conduct tests per the Powertrain Diagnostic Procedures
service manual.
² A misadjusted brake (stop) lamp switch. This could also cause an intermittent problem.
² Loose, damaged or corroded electrical connections at the servo (if used). Corrosion should be removed from
electrical terminals and a light coating of Mopar T MultiPurpose Grease, or equivalent, applied.
² Leaking vacuum reservoir (if used).
² Loose or leaking vacuum hoses or connections (if used).
² Defective one-way vacuum check valve (if used).
² Secure attachment of both ends of the speed control servo cable (if used).
² Smooth operation of throttle linkage (if used) and throttle body air valve.
² Failed speed control servo (if used). Do the servo vacuum test.
CAUTION: When test probing for voltage or continuity at electrical connectors, care must be taken not to
damage connector, terminals or seals. If these components are damaged, intermittent or complete system
failure may occur.

Thanks Bill so I gather from this since this is controled by the ECM/PCM that it will be one of the dills that the dealer will have to fix with computers..

There's probably a flash available to fix the issue. If that's all it is, be around a half an hour. Or worst case, need a new PCM ($400ish) or a new ECM (around a grand).

Ok thanks Bill! I just got off the phone with the dealership they said to bring it in tomorrow and they'll see what's wrong with it.. I figured they would. they have the best customer service, and vehicle service center i've ever dealt with...

A misadjusted brake (stop) lamp switch. This could also cause an intermittent problem.


Read more: https://www.dieselbombers.com/5-9-li...#ixzz0XhveTYPt

save a little time you could just check the brake switch see as i was reading that I was thinking that it may be the brake switch? worth a shot to look and see if your brake lights lash if you just tap on the brakes with your hand.

I had this SAME problem for the last 7 months! :argh:

Nobody could figure out why it was doing it, till one day the APPS sensor went out. Got it replaced and ever since it has worked! Cost was $700 installed at the dealership.

not to hijack here, but you can set a high idel off the cruise control with these trucks? i can do it with SOME of our internat. at work, but i never had any luck with my dodge.

It has to be enabled by the dealer.