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Discussion Starter #1 (Edited)
Ok, my Cruise Control never has worked (Holding SET with the desired speed), I saw a post about restoring CC and I started diagnosing, first, I checked the service manual procedures, I made a simple Code Puller tool and tried the manual tests (mainly input/CC computer self diagnosis).



It doesn't throw any code, just a continuous flashing as it should when there is no trouble codes.



Then I did the Input testing with all the items in that list (cruise control switches are ok, tps, closed throttle, speed sensor, brake, clutch switch):




Someone suggested checking the relay:



Its working.


Also checking the actuator and vac hose (suck that one lol..)



The throttle plate moves and there's no leak on the hose.

Then, I inspected the vac pump:



both solenoids work, I can turn on the pump and there is vacuum on the lower nipple/port (the one that can rotate), now.. the L shaped vac line is there but if I turn the pump on (12V on pins 1 - 4), the throttle/plate doesn't move, if I connect the vac line from the actuator directly to the lower pump nipple (rotating one) it easily opens the throttle, it seems that there is minimal air flow between the lower nipple and output one (to the CC actuator)

Any help on this, what else can fail in the CC system? :shitsweak:
 

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I havn't worked on Mitsu cruise controls..never had a issue but on most I did work on it was brake or clutch cancel switch, usually you could get up to speed and lift up on the pedal with your toe and see if it engages...some were just adj. other bad swich.

I don't know that these cars have a vacume release valve on the brake pedal but I had that issue on some cars that had vac loss to servo and I think I had one tied to a brake booster valve or booster.

Only had on/off/set/resume switch failures on domestic cars.
 

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Discussion Starter #3
I'm gonna try that, I performed the tests with the car stopped, there is a Closed Throttle switch, throttle position sensor, brake and clutch switch (extra one on the clutch, its not the same for starting protection), I read that sometimes you can pull the clutch like that and CC engages but never tried that on the Brake pedal.
 

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The switches are simple to test just on/off.

Brake switch on my Stratus wore out and the car wouldn't go into overdrive (auto trans).
If I wanted OD I had to lift the brake pedal up/dwn a couple times.
 

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Discussion Starter #6
I tested the switches using the CC onboard diagnostic and those worked, but It makes sense, maybe the pedal moves when the car is on and the booster is working.

I don't get any codes on the diagnostic, just the normal on/off with 0.5s delay but... I didn't grasp the vac pump operation, does it need to pull the throttle when power is applied at terminals 1-4?
It just turns on and there is vacuum on the lower nipple, maybe the solenoid will route that to the output nipple that is connected to the actuator?

I tried turning the vac pump ON and also activating the solenoids with no change, it just get rid of the throttle cable slack, I did all the tests with a PC power supply, I wasn't comfortable shorting battery cables :p


That connector should look similar to A-28/C-61 right?
 

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Discussion Starter #7
Update..

well I checked all the wiring in that diagram, grounding pin 23 turns the cruise indicator and cruise relay, I can ground 26, 13, 12, pump works and both solenoids turn on (with the main relay active), sounds like a Computer issue (it looks fine inside), Im on my way tothe junkyard.. I try the cruise control set button and it engages... some bad connection at the cruise control computer plug... 20 year old wiring, you never know :)

By the way, its a pretty good system.
 

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Discussion Starter #9
I was lucky, mine was working, I pulled one form a parts car and trashed the switch/clockspring, I tested by the manual with the gatecrasher DIY cable plus the Cruise Computer output (led).

 
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