97 Pete problems

[GOODE11]

Hey guys anyone run a newer electronically controlled Pete 379 w/ the 3406E in it?

My switched auto-fan clutch quit working and the switched electronic high-idle control quit working.



To explain further:



In my rig the high idle and cruise are on the same 2 toggles, one to turn it on/off and 1 to set/accel/decel. Funny thing is I used the cruise coming home and before shutdown I was going to cool her off w/ the high idle, and guess what; no high idle.



My fan toggle lets you turn it from on/auto, it works on the manual side and it kicks on w/ the ac on auto but not during normal operation.



Anybody know where to look? This electronic stuff is for the birds!



I really hope someone knows, Peterbilt just stuck me over leaking injector cups a few days ago and I do not want to go back.



Thanks



David

 

[FFutch]

How many miles...

... the injector cups should have been under warranty. I know we did a crapload of them on Cats dime. As far as the fan problem,unless you have access to a pro-link,about all you can do is check the switch connections and fuses. K. W. 's had the back-up light and auto. fan on the same circuit. The truck would come in for auto fan not working,would check over all electrical fan connections and find nothing. Install fuse and run in shop,all was fine. Go to back out for road test,pop the fuse again. Found shorted wires at tailights. Since Pete and K. W. are both paccar just something to check... . Doug

 

[GOODE11]

FFutch, I only got 25% parts/labor for a warranty from Cat. I was 8 months out of the 5yr, but only sitting at 420,000mi.



I don't have backup lights but I'll check for some bad connections. A neighbor following me home yesterday said my brake lights were staying on. I wonder if this could be connected to the other problems?



I forgot to add that Pete here in KC said it was a electrical problem after some testing they did. I was already way over budget so I couldn't let them go farther.



I really feel sorry for the guys running new trucks after the Oct 1 deadline.



FFutch, thanks for the response and info. I was really hoping to find a bad sensor or something.

Any idea where the sensors/switches are for these two systems?



Thanks again--

 

[The patriot]

If youre in good with the place doing the warranty work, they can make the warranty "good" for ya.

Eric

 

[FFutch]

The fan stat should be on the thermostat housing where the top radiator hose goes in. It should have 2 wires going to it,one side might be split into 2 wires. You should have juice on one side with the key on. If not then a blown fuse or broken wire. Next jump across the stat and the fan should come on or you should hear the solenoid kick in. You said it was working on manual and with the a. c. so this leads me to believe that the problem is on the fuse side. The K. W. back-up lights would always short in the tailight housing so check there first on your Pete. Also I can't remember what kind of power distribution box that Pete has(I worked at a K. W. shop)but we had problems sometimes in the p. d. boxes behind the fuses,which we rebuilt,which almost has to be done at a dealer. Hope this helps. Too bad you aren't a little closer to western Maryland or I would help you out... Doug

 

[bbowe]

Brake Pressure Switch?

There is an air pressure switch under the cab either in or near the brake valve (I too only really know KW, where it is in the dash) that signals the brake lights and tells the Engine ECU to turn off the cruise. If that switch is stuck in the on position your brake lights will stick on and the cruise and high idle won't work.



If the fan turns on and off automatically, but you have no manual control, it is probably switch wiring like mentioned above.

 

[GOODE11]

Sounds like I need to buy a KW. I would of but I couldn't find a good one around, I really like the older KW's.



Could you guys tell me where the fuses would be for the switches on the panel? I've checked every fuse I can find and there isn't one blown nor is there any specific one for the switches. I've checked the "fuse panel" on the driver side kick panel and the four behind the switch panel.



I had some broken wires in the harness worn through, and I repaired them this evening. Still no high idle or auto fan, I had my hopes up too!



Thanks for the info guys, I really appreciate it. I'll post as soon as I do the checks mentioned by you.



Thanks-



David

 

[E7mack96]

BBowe is right!!!

Mack uses the same setup and I had the same problem on my '96. In my case, the ecu would not know I hit the brakes, and the cruise would try to overpower the brakes until a set Torque threshold was crossed, causing the cruise to dis-engage and de-activating high idle as well... . I also got an Engine Malfunction light. The code set said the brake pressure sensor was bad.



Hope this helps

 

[Rambunctious]

Electrical problem

There are only two thing that can disable the high idle and cruise and that is the brake pressure switch and the clutch switch. If you have jake brakes and they still work then it is proably the brake pressure switch. All you have to now is locate the switch which is behind the steering column on the floor which is accessed by removing the two plastic steering surrounds.

Hope this helps.



Chuck

 

[GOODE11]

Thanks for the replies everyone! I have fixed the high idle/cruise problem from your great responses.



Now how about the auto-fan not coming on? I had a few wires rubbed through on the engine wiring harness, but I fixed those and it still doesn't work. Where are the sensor(s) that run it and how do I test them if its possible?



Thanks a lot I appreciate the info--