trouble codes and electrical troubles

[Jimmy]

I am new to world of diesel's. I have 1994 Chev 3500 dually with a 5 speed, with 154000 miles. I have trouble codes of 36, 41 and 78. What are these and how do i fix them ? I also have a electrical problem. When I turn on the headlights my light on the clock dim's and the turn signal indicator on the right side comes on. The turn signal won't work on that side. If I turn off lights the turn signal indicator work fine and the clock light is bright again. Where should i start looking for trouble. Thank you.

[6point5]

Jimmy:

You need to try to fix the electrical problem before worrying about the other stuff. The codes refer to the Pump/PMD (36), the brake light switch(41) and the wastegate solonoid (78). I'd start with 2 things. 1, remove and clean all grounds that you can find, including the batteries. 2nd, I take a real good look around in the cab for a short around the brake pedal and under the dash or something loose or bent by a kick from your feet. Also, if you have a trailer light plug going to the back, look it over good for wounds and corrosion. Look around the headlight switch and the wire harness going into the steering column. My experience is that any little electrical glitch can severely affect the accuracy of any codes. Spending some time like I suggested probably will be $$ well spent. Once you start replacing parts because of chasing codes, the cost goes up and many of the parts I have purchased were not the problem anyway. Good luck!

[Chevylover]

DTC 36 - Injection Pulse Width Error (Response Time Long)
PMD fault - replace


DTC 41 - Brake Switch Circuit Fault
could be ground problem


DTC 78 - Turbo Wastegate Solenoid Fault
Solenoid fault - replace
or
plastic vacuum hose leak - replace


Have just seen that 6point5 was a little faster in answering. He's right. Try what he wrote and if the codes comes back check the other possibility's.


Cu,
Sven

[bbtlr3]

Just so you don't worry too much about the clock, it is supposed to dim when the lights are turned on along with the A/C control display.

[christja]

The stock clock will dim with the dimmer control

[sixnickel]

1st the radio does dim with the head lights on, in the day time you need the bright display so you can see it. In the dark it would be blinding!! 2nd You have a bad ground on the right side marker light circuit. It's probably a bad light socket front or rear. With the lights on and the sockets out have a helper watch the turn signal indicator take a jumper and ground the bulb base, when you ground the one with the bad ground the the indicator will go out. Or with the lights on turn signal on, ground the bad one and everything will work normal. find the problem and fix the round. The Golden Rule is when things act normal it could be the positive side when things act wacky and don't make sence check the GROUNDS.

[RENGRAB]

Hello

My silverado 1995 6.5 diesel, are having the codes 33 and 45 concerning the egr, i changed the hoses, but still the light of the ses again, what else can I do to solve this problem

[Chevylover]

Sounds like bad EGR solenoid(s).

Cu,
Sven

[torque454]

My sub. has a dimmer switch (and i assume the rest of these trucks do too) beside the headlight switch. Push it all the way up, everything should be bright. If it isnt, push the switch up more. There are two detents in it, the 2nd one should make it bright again. It does in mine...