[Bssrboss]

Edit: One problem fixed, new major one!Right side flashers & p0540 code help!

Hi everyone,

Please see down for new problem!

New to the forum, been trolling for a while, you guys were a huge help recently with an Egr problem I had. Awesome site! :rockin

I'll start off with my infos:
2007 classic 2500hd
6.6 lbz
crewcab 4 x 4
70,000 kms.

K so here is my problem,

Was installing my new egr valve today and as i was putting the top end back together i accidentally touched the power cable that goes to the air intake heater relay to metal and i believe i blew the 175 amp mega fuse. the wire no longer has any power to it. After I finished putting everything back together I hooked up the scanner and got code p0540. Now I'm sure it's just that i blew the fuse, however i cannot find the relay or fuse anywhere. Anyone have any ideas were it might be, and how hard it is to change?
Truck seemed to run just fine, but I am getting a CEL on the dash.

Also, My entire right side of the truck, The flashers work "sometimes" They always work on the left side, but more often then not the front, rear and mirror right will not work. Sometimes it'll work once or twice, then will just stop. I thought it might be my switch, but i brought it to my mecanic and he said the switch was fine. also, when I have my trailer hooked up the lights always work on the trailer, but not on the truck, inside the truck the right flasher flashes fast like a bulb is burnt out (only when a trailer is hooked up, when its not, nothing comes up on the dash)...... Anyone have any ideas, I'm an electrical 0!

Thanks in advance!

 

[Len Todd]

Did you check all the fuses in the Under-hood fuse box? If I recall correctly, there is a separate fuse for the Air Intake Heater. If you blew the mega fuse, I think you would have lost more circuits. Truck would probably not run. If it did, you would certainly have more than one code.

Regarding the lights, it sounds like you have a loose ground or bad connection someplace on the problem side of the vehicle. Did this turn signal problem start right after you shorted the Air Heater cable? Or was this a pre-existing problem?

 

[Bssrboss]

Yup I checked and double checked every fuse in the under hood box as well as in the drivers side door. none of them are blown, i also hooked up the voltmeter to the power cable that i shorted out with in the firstplace and it has no power to it at all, it usually has power at all times, even when the truck it off, thats why i think its the relay of fuse i blew.

flashers were a pre existing problem

 

[Len Todd]

I am not sure of the mega fuse location on your truck. But, ... I think they showed them on the firewall on the passengerside. I'll go take a look at the Tech manual and see if I can find it quick. Don't suppose you could trace the wire back? I'll bet you get to the fuse fairly quickly.

 

[Bssrboss]

tried that but it tucks under where the boost/ ground point is to the left of the main battery and i cant follow it any further without ripping off more parts.

I really appreciate all the help

 

[Len Todd]

Mega fuses are located under a small square plastic cover above the battery on the passenger side, right on the firewall. The power comes from the battery, through a mega fuse to the Intake Air Heater. Follow the Red wires. There is a another mega fuse for the glowplug module in the same fuse block

 

[jc1843]

The turn signal light problem is probably the flasher-- it is located under the left side of the dash!

 

[Bssrboss]

Ok, This truck is turning into a nightmare.

So the p0540 code was in fact the 175amp mega fuse that was located underneath the under hood fusebox. I need to remove the driver side engine bracket and the fuse box cover to access it. So replaced that, all fixed. drove it for 30 miles and threw another code. p0299. turbo underboost. hmmmmm, thinking nothing of it i cleared the code and continued on my way. About 2 miles later the engine started to whine really loud, like driving on a cold start, so i pulled into an empty parking lot and shut off the truck and turned it back on, no CEL no more whining. tested it in the parking lot, and ...... at 3000 rpm there is a huge banging noise like the engine is backfiring and some white smoke. does it every time i hit 3000 rpm. Brought the truck home right away and now here i am... Did I not put something back together correctly when doing the egr valve? is it something to do with the intake? currently there is no CEL but whenever i hit 3000 rpm it sounds like the truck is gonna die! Help!