To start off, I'm leaning toward the headlight switch or the ignition switch.

Now on to the issues.
This happened one other time a couple months ago and I pulled the fuses for the off road lights and it didn't happen again until today.

I noticed there was something wrong when I opened my door and the dome light didn't turn on.
I turned on the headlights and got the dome back and it seemed fine.

Right after I turned on my fog lights the radio cut off then turned back on and the headlights flicked off then right back on. This was after driving for a couple minutes.

After I got home and went to restart after a few minutes the dome light didn't turn on and turning the headlights on didn't help either.
I turned the key to the on position and nothing came on (dash/dome/headlights).
When I turned the key back off I heard "click click click click" coming from the steering column so I turned the key back on and the clicking stopped but nothing came on again.
I screwed with the key (on/off/on/off) and switched the headlights on and off a couple times along with messing with the **** to turn the cab lights on a couple times and it eventually went back to normal.

To add to the confusion, two times I started the truck out of about 10 I had a bit of a weak start. The truck started and the engine sounded like it dipped about 200 rpms for just a second right after it turned over then went back to normal.

So does anyone have a clue for me?

To add to this, I started the truck about 6 times after pulling the fog light relay out and it didn't do it again so that's why I'm thinking it might have something to do with them.

This is how I have my fog lights connected

 

In the FUSE BOX, there's a TIME DELAY RELAY. I've got to look at the scematics again because, I can't recall WHICH CKT/s are off of that other than the DOME CKT.

It sounds like a supply problem to me or, more specifically, the loss of source / ground to complete the CKT or a RELAY cutting out.

EDIT: I just went through and, that's tied to the ignition switch at the KEY IN SENSE and HALO LAMP CKT, DOME CKT, CARGO CKT, and last but not least, HEADLAMP SWITCH.

<IF> you heard clicking, that's most likely due to a RELAY that's not energizing to full capacity thus, opening and closing rapidly. What may be happening is, the SOURCE for that RELAY or, the CKT may be overloaded thus, exceeding the current rating on that shared CKT thus, dropping voltage to this relay thus, losing the connection intermittently until the load returns to normal.

CM

 

I checked the PDC and the fuse box in the dash and I don't see a time delay relay. I did see the blue relay in the dash fuse panel that isn't labeled on the cover, is that it?

I also spent some time looking in the 2001 service manual and I'm just lost trying to find the relay you're referring to.

Which schematics are you looking at? It sounds like you found the source of my problem but I can't find it.

 

I had another issue with it today. I drove about a half mile and the radio started resetting so I turned it off. Then another half mile down the road I got a chime and the check gauges light and my voltage was at 18v. So I yanked it off the road and cut it off.
When I opened the door I heard the clicking from under the dash (it only does it with the door open) and the dome light didn't work along with the headlights and the key was unresponsive aside from making the clicking stop when I turned to the on position.

I found out that the clicking is coming from the central timer module and the way I got it to stop clicking was by turning off the dome light.

After inspecting all the fuses and messing with the key and lights I finally decided to check the battery terminals. When I pulled them off they had that light shiny/powdery corrosion on them between the battery post and the terminal.
I scraped them clean with a flathead screwdriver and reconnected them then the truck ran like nothing even happened.

cmckenna, do you think the corroded battery connections could be the source of my issues?

 

Sure. Yes, I do and, here's what can happen under that condition.

VOLTAGE DROP due to high resistance is the No 1 issue among all vehicles and, half the time, it's at the battery level. Either the cable is corroded UNDER the insulation down a couple of feet or, the ends are no good or, the interface at the BAT connections is loaded with oxides and carbon build up on the posts such as in your case.

The only thing that DOES NOT make sense is, why the PCM did not cut out as well. I don't know about your year in particular but, according to my schematics of the ignition system, the PCM is run off of the FUEL PUMP fuse as it's ONLY source of direct power to the BAT.

In your case, CKT 1, FUSE 1, off of that feeds another fuse and, I believe it's the IOD fuse (FUSE No 17) and, from that, it feeds the dome and headlamp switch. Also off of that is the TIME DELAY RELAY and KEY SENSE CKT as well. It's all tied into FUSE No 1 which, as you may or may not know, this is the SOURCE off the BAT / Generator as are all the fused CKTs at the PDC.

It's one common RAIL that ties all the HOT side of the fuses together so, if you've got a power loss / voltage drop, it will be seen across the board. This includes the PCM.

Now, the question is: Why did your radio cut out? If that's tied to CKT 1, FUSE 1, well, to me, it sounds like a supply issue BUT, IF: you TAPPED into another power source OTHER than the one dedicated off the RADIO FUSE, then, I can see why the stereo also shut off. It's tied into that common CKT that the headlamps are on as well.

The next question you need to ask is: Why am I seeing 18V! That's a huge indicator right there that somehting is totally out of whack.

You can have a short to ground but, not without popping a fuse.

You can have a partial short to ground - thus NOT popping a fuse BUT, not without VOLTAGE LOSS. You short anything out on the same CKT, (even partially) and watch all the lights DIM- THE VOLTAGE DROPS! IT does NOT increase so, we have something going on with seeing 18V.

In my experience, there's only ONE thing that will produce a HIGHER VOLTAGE and that is: THE VOLTAGE REGULATOR. When wide open they don't level the voltage and, as a result, they allow FULL output of the generator to be seen at the AMP gauge.

But, let's look at WHERE this VR is! It's inside the PCM and, if the PCM is NOT getting full power, guess what? Yeah, that's correct, the voltage is going to be lower than what is considered "withing normal operating limits" thus, there goes your regulator function thus, the possibility of witnessing 18 VDC at the AMMETER.

So, again, I would keep a CLOSE eye on that amp meter as well as running some simple tests as outlined below.

TESTING:

-Disconnet the NEG (-) BAT lead. Wait a minimum of 20 minutes. (There's a system in the vehicle that is going to store a charge)

-Disconnet the RED (+) BAT lead.

TEST FOR SHORT:

Using a DMM, measure the OHMs across the cables. This is going to test for DEAD SHORT. The closer to zero the reading is, the worse the short.

TEST FOR HIGH IOD

-Reconnect the RED (+) BAT lead.

-Set the DMM to AMP (remember to move the probe to AMP)

-Set meter to 10A

-Place one probe TO THE BAT first. (if it's going to spark, you don't want to spark near the battery for, if there's battery vapors, it could ignite and explode)

-Connect the remaining probe to the NEG BAT cable as far away from the battery as possible.

-Note AMP / CURRENT DRAW with VEHICLE OFF and KEY OUT OF IGNITION.

NOTE: OEM spec is ~.035A.

CM

 

Thank god for guys like you cmckenna what an asset to have here!

I'm not much help dealing with an issue such as this but Sheriff on a somewhat related note, do you have all 4 lights running off 1 post on that relay? When I wired up my rollbar lights I used one of the relays with the 87 and 87A terminals and ran each light off its own post. I have NO idea if it would make any difference in your setup though, and I imagine it's apparently not the issue here, but I thought I'd throw that out there....

 

I'll test those things tomorrow when I get off work, thanks.

The last time I saw the voltage spike to 18v (about 4 years ago) it was from a loose negative cable arcing to the battery post.

I forgot to mention that while the clicking was going on, nothing worked. Meaning none of the cluster lights, dome light, headlights, chime and the fuel pump, it was like I had a dead battery. At one point the clicking stopped and the dome light and the odometer came back on but they were very dim.

I'm going to clean the battery posts with a wire brush while I'm testing since the screwdriver didn't get them completely clean. Hopefully I don't have a short somewhere and it's just the corroded battery posts that are giving me a fuss.

Maxx, I do have all four fog lights running off the 87 post on the relay but the amp draw is significantly lower than what the relay is rated for. I pulled the fuses and the relay for the lights when my issue began so there is no power to the relays meaning no power to the lights.

 

This is what was missing from the first go-around. This is essential in diagnosing and, this is a HUGE indicator of a TOTAL LOSS OF SOURCE.

INCIDENT: TOTAL LOSS OF POWER resulting in VOLTAGE spike as a result of IN RUSH current.

PROBABLE ROOT CAUSE: Loose or corroded battery cables or poor connection/s (hot or ground at or near SOURCE.

SHORT TERM FIX: scratched battery posts with screwdriver

RESULTS: Vehicle came back to life and has not indicated sign of failure- YET. More testing needed.

RECOMMENDED ACTION ITEM: thoroughly clean inside battery cables and posts with BAT cleaning brush. Apply corrosion resistant chemical to prevent oxide build up. Monitor this over a period of time. Should be fine if this was the ROOT CAUSE for failure.

CM

 

Nice job CM
Only thing I can add here is that you need 80% of rated volts for a relay to energize reliably. anything less and you will have slow shifting of the contacts and or chatter.

 

I did the tests.

Battery voltage is 12.26

Short test showed 1.12-1.15 ohms.

IOD test showed 0 amps. Both battery cables connected, meter set to amps key off, doors shut with the dome light off.

I pulled the IOD fuse out and it isn't blown.

Everything seems to be working though.