I just finished doing a lot of work under the hood and under the dash. I replaced both negative battery cables as the clamps were cracked, cleaned up the battery boxes and under the boxes, and replaced the hold down brackets that were corroded.

Next I installed the Summit headlight wiring harness and finally finished connecting my gauges for boost and pyro (wires/lines have been run for a while) as I had the dashboard apart for installing aftermarket silver-faced gauges and connected all of that wiring. I made sure all tools were collected up and insured there were no lose wires. (Good thing as the passenger side Summit harness ground was hanging loose... forgot to ground it.)

After I'd finished reconnecting the batteries, I turned the headlights on and off to see if they worked; they did, but I didn't start it. The lights were off when I went inside. When I went back out to the truck about 10 minutes later, it is completely DEAD. No lights, no start, no nothing! Turn the key and there's NOTHING. What could have caused this? I checked the main fuse box under the hood and all of those fuses are good. I have not yet checked the interior fuse box but not sure if anything in there would cause the truck to completely die...

Unfortunately, I have to head to an appt and will be back in a few hours... ugh...

Thanks in advance!
Dave

 

I think that you have some fuseable links coming off the battery , but you should double check that what ever blew it 1st. , with that much wiring work just being done it could be a job to find , but you do have some advantage - you did the work , of course , sometimes it takes a fresh mind to find what the last one did, just poke around till ya find it.

 

Is it obvious if the fuseable links are blown? If they are blown, would that kill the entire truck? It acts as if both negative cables have been disconnected... Thanks!!

 

The wires (links) will look melted in the first foot from the battery if they have blown.

 

Fueseable links look/feel good... I'm going to pull all of the battery cables, clean clamps and terminals, and reattach and see what happens... Not sure what else could have caused the truck to completely die like this...

 

No jiuce at all? Could you have drained both batteries with a direct-to-ground? That would probably melt some things in the process....but it wouldn't hurt to check the V out of the batteries...

Is there a single main fuse that COULD completely isolate the batteries from providing power to anything?

 

That was my question... Is there one thing short of disconnecting the negative cables that would totally kill the truck?

The batteries worked fine before I spent about 5 minutes in the house. I'd checked the headlights after connecting the batteries; both were bright. Turned off the lights, went inside to get some things, came out and loaded the truck, then tried to start it. Nothing. No starter, no lights, etc. I didn't have time to pull out a voltmeter but will try that tomorrow. Had something come up suddenly and can't get to it today... (when it rains, it pours...)

 

I haven't seen a reply about the batteries , are they still charged or dead ?
with hot batteries , use a test light and probe till lite does not go on .
If the batt. are dead then disconnect & charge , connect one and look for , no feel for something warm-hot [short] thats if it didn't burn a fuse ,a connectoin , wire ect.
What about the fuse relay box under hood ? I do not want to asume anything becouse if you asume then you look everywhere els forever.
As soon as you get charged batt. use test lite till you find the lost connection , pos. or neg.

 

Finally got to get back to the truck this afternoon with a voltmeter. Batteries were good. Grounds were good. Turns out, the main positive cable and terminal had enough gunk on them that when I put the clamp on, there was not enough connection for it to work. It was probably just a fluke that I had lights for a few seconds. Once I cleaned all four terminals/clamps and reconnected everything, it all worked fine!

Another problem, though... my NEW pyro gauge won't come up more than about a millimeter off of the peg, even at WOT on the highway... There was a pyro lead already installed on the truck that I used with a new gauge. Probably have to buy another one unless someone can come up with something I could have done wrong... Installation was done according to the instructions.

 

Check your splice connections to make sure they are insulated from shorting or grounding.
I've seen dirty batt cables do that many times. Glad to hear you got it running.

 

- sounds like the existing pyro probe is not compatible with your new gauge, it will have a set output range for the through-scale temperatures....

 

Thanks Howard! Yeah, I checked everything before assembly as I had installed all the wiring months ago. Everything was good as far as I could tell. My worry is what Rauschbo said... that I'll need a new pyro probe...

 

Check with your new gauge, most new ones come with an isolator or generator that takes the minute voltage from a pyro sensor and amplifies it for the gauge, it also makes it safer against shorts and such. Older ones connect straight to the probe.

 

Yes, mine came with an amplifier. I did get a note back from Diesel Manor (who I bought the gauges from) that the probe I have should be compatable, so I just need to break down and pull the a-pillar off and see if the wire came loose during installation of the pillar...