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cruise control light on not working

Posted: Tue Nov 10, 2009 12:29 am
by caliass
I have a sxt 2003 mtx, the cc light comes on when I activate it, but it wont set a speed at all.

Any suggestions?

Posted: Tue Nov 10, 2009 1:06 am
by Swordfish2Cowboy
Check the hoses and cables.

Posted: Tue Nov 10, 2009 8:32 am
by Jenni
check if the cables from the throttle bvody to the vacuum canister aren't stuck. i had that problem

Posted: Tue Nov 10, 2009 1:43 pm
by caliass
checked cables, they seem to be ok, still not working, what should I do next?

Posted: Tue Nov 10, 2009 1:54 pm
by occasional demons
Check the servo diaphragm for a leak. Or the lines going to it, for that matter. Unless you have a vacuum pump, you may need to get personal to see if the diaphragm is holding vacuum.

Posted: Tue Nov 10, 2009 3:31 pm
by caliass
Thanks Guys,

I had to go to work but I will check on that servo as soon as I get home. I will post anything that happens.

Posted: Tue Nov 10, 2009 4:14 pm
by FAC3L3SS
When mine did that, it'd only set for like 5 or 6 seconds, then stop. My clutch was going out.

Posted: Tue Nov 10, 2009 9:28 pm
by occasional demons
FAC3L3SS wrote:When mine did that, it'd only set for like 5 or 6 seconds, then stop. My clutch was going out.
It will shut down automatically for a dozen reasons, but it usually sets first.

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
per second (indicates that the co-efficient of friction
between the road surface and tires is extremely low)
² The speed signal decreases at a rate of 10 mph
per second (indicates that the vehicle may have
decelerated at an extremely high rate)
² If the actual speed is greater than 20 mph over
the set speed.
² Autostick shifts into 1st or 2nd gear (autostick,
if equipped)
Once the speed control has been disengaged,
depressing the RESUME switch when speed is
greater than 20 mph allows the vehicle to resume
control to the target speed that was stored in the
PCM.
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.
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.
A little light reading...
OPERATION
The PCM controls the solenoid valve body. The
solenoid valve body controls the application and
release of vacuum to the diaphragm of the vacuum
servo. The servo unit cannot be repaired and is serviced
only as a complete assembly.
Power is supplied to the servo by the PCM through
the brake switch. The PCM controls the ground path
for the vacuum and vent solenoids.
The dump solenoid is energized anytime it receives
power. If power to the dump solenoid is interrupted,
the solenoid dumps vacuum in the servo. This provides
a safety backup to the vent and vacuum solenoids.
The vacuum and vent solenoids must be grounded
by the PCM to operate. When the PCM grounds the
vacuum servo solenoid, the solenoid allows vacuum
to enter the servo and pull open the throttle plate
using the cable. When the PCM breaks the ground,
the solenoid closes and no more vacuum is allowed to
enter the servo. The PCM also operates the vent solenoid
via ground. The vent solenoid opens and closes a
passage to bleed or hold vacuum in the servo as
required.
The PCM cycles the vacuum and vent solenoids to
maintain the set speed, or to accelerate and decelerate
the vehicle. To increase throttle opening, the
PCM grounds the vacuum and vent solenoids. To
decrease throttle opening, the PCM removes the
grounds from the vacuum and vent solenoids.

Posted: Wed Nov 11, 2009 12:14 am
by caliass
The servo and lines look good, how do I check the brake switch?

Posted: Thu Nov 12, 2009 12:06 am
by caliass
I am still trying to figure out what to check on the brake switch, does anyone know what I am looking for thats out of the ordinary?

thanks for all your help, this forum is worth its weight in gold!

Posted: Thu Nov 12, 2009 8:24 am
by occasional demons
From the diagram, it is the Yellow/Red tracer (PCM to Brake Switch) switched to Dark Blue/Red tracer (Brake Switch to Speed Control Servo)

GL!

Posted: Thu Nov 12, 2009 10:44 am
by Swordfish2Cowboy
Where do I get one of these autostick Neons? :D

Posted: Thu Nov 12, 2009 12:05 pm
by caliass
I am back at work so I will check on the brake switch @ 7 pm tonight and post the results.

Posted: Thu Nov 12, 2009 12:12 pm
by occasional demons
Swordfish2Cowboy wrote:Where do I get one of these autostick Neons? :D
Custom built. My guess is it is a generic guide for any Dodge. I say only Dodge, because my Jeep does not have the same features as Dodge Speed Control. (Such as auto downshift to maintain set speed.) Pontiac G6's won't downshift either. And I thought GM cruise control was sooo much better. :roll:

Posted: Thu Nov 12, 2009 9:17 pm
by caliass
Hey guys,

I am throwing the towel in for the night, the weather out here in California has taken a turn for the worst, and I have been out(away from a proper winter) here too long to keep working in inclement weather. I used to replace head gaskets in sub zero conditions , but my blood has thinned waaay too much.
more info tommorow.

Posted: Fri Nov 13, 2009 9:52 pm
by caliass
I went over all the connections and still cannot find anything out of the ordinary, no corrosion or any sort of stuff I would have expected from living back east. It is a desert like environment out here. The only thing left to check is the switch on the steering wheel, but it looks like I have to take off the air bag to do so. I can't do this till monday as I work weekends. Any more suggestions?

Posted: Sun Nov 15, 2009 6:40 pm
by occasional demons
Check the switch for the "cancel" button. If it is stuck, it might not let anything set, but the indicator may still be lit.

Posted: Sun Nov 15, 2009 11:18 pm
by caliass
I have been staring at it for awhile now and was thinking about that (the actual switch). I have to take the front cover of the steering wheel and the air bag off right? Or could I do a very careful mechanical manipulation to the cover to check the cancel switch.
Any ideas?

Posted: Mon Nov 16, 2009 12:30 am
by srtjesse
check your codes i had a problem with my brake switch that was driving me crazy i pulled it off and took it apart i moved things around put it back and now my cruise works and i have not gotten the p7024 code in over a month knock on wood i think i just fixed my problem lol hope this helps

codes

Posted: Sat Nov 21, 2009 7:19 pm
by caliass
I currently do not have a check engine light on. these cc codes, will they show up using the ignition on/off sequence?

Posted: Sat Nov 21, 2009 7:23 pm
by srtjesse
o snap i cant remember i havent had them in over a month haha

Posted: Sun Nov 22, 2009 5:38 am
by srtjesse
yeah if you do the on off on off on off key dance they will show up i cant remember what the code was tho

Posted: Sun Nov 22, 2009 2:31 pm
by Mopar00Neon
occasional demons wrote:
Swordfish2Cowboy wrote:Where do I get one of these autostick Neons? :D
Custom built. My guess is it is a generic guide for any Dodge. I say only Dodge, because my Jeep does not have the same features as Dodge Speed Control. (Such as auto downshift to maintain set speed.) Pontiac G6's won't downshift either. And I thought GM cruise control was sooo much better. :roll:
There were in fact, autostick Neons. AFAIK, all export only (and export, as far as also having the tails, rear bumper, etc)

Ive got pictures somewhere.....

Posted: Sun Nov 22, 2009 4:41 pm
by occasional demons
srtjesse wrote:yeah if you do the on off on off on key dance they will show up i cant remember what the code was tho
Fixed. last key on, stays on. There would be codes for solenoid circuits, etc. depends on NGC or not. IIRC, NGC has more codes...