RTH!: Turn on headlights, 80 dies!!?? (1 Viewer)

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I have searched and have not been able to find a similar issue. So here goes:


This part maybe unrelated, but trying to tell the whole story here...Last week i removed the driver's front seat to program the 2meter radio mounted underneath it. All wen well but noticed my windows, door locks and map light did not work. Found that the 30amp fuse was blown. Replaced the fuse and all appeared to be well. (Again, this part of the story may be completely unrelated to my problem).

Fast forward to Weds. This was my first time driving with the headlights on and when i turned them on (with the truck running at speed) the radio shut off then came back on and the truck stuttered like it wanted to die. Once they were on the truck ran normally. If i hit the high beams or hit my PIAA lights as a test, the truck would almost die at highway speeds, and the dash lights would all come on for a moment. If i performed this same test at idle, the truck would die.

When i go home, the issue was gone and it had been gone for 2 days so i chalked it up to a fluck.....It came back yesterday evening. Got home OK and played with the lights, got the same results and got the ECU, clock and radio to reset in the process.

I am a (1) :wrench: guy hoping someone might be able to send me down the right path of trouble shooting. As the problem seems intermittent, i am guessing it could be a bad or loose ground? Alternator perhaps? The battery is 2 years old i believe and is a group 31 Sears Platinum.

Any help would be appreciated as i am trying to prep for a small trip next weekend.

Thank you!
Sean
 
I have searched and have not been able to find a similar issue. So here goes:


This part maybe unrelated, but trying to tell the whole story here...Last week i removed the driver's front seat to program the 2meter radio mounted underneath it. All wen well but noticed my windows, door locks and map light did not work. Found that the 30amp fuse was blown. Replaced the fuse and all appeared to be well. (Again, this part of the story may be completely unrelated to my problem).

Fast forward to Weds. This was my first time driving with the headlights on and when i turned them on (with the truck running at speed) the radio shut off then came back on and the truck stuttered like it wanted to die. Once they were on the truck ran normally. If i hit the high beams or hit my PIAA lights as a test, the truck would almost die at highway speeds, and the dash lights would all come on for a moment. If i performed this same test at idle, the truck would die.

When i go home, the issue was gone and it had been gone for 2 days so i chalked it up to a fluck.....It came back yesterday evening. Got home OK and played with the lights, got the same results and got the ECU, clock and radio to reset in the process.

I am a (1) :wrench: guy hoping someone might be able to send me down the right path of trouble shooting. As the problem seems intermittent, i am guessing it could be a bad or loose ground? Alternator perhaps? The battery is 2 years old i believe and is a group 31 Sears Platinum.

Any help would be appreciated as i am trying to prep for a small trip next weekend.

Thank you!
Sean

sounds like you might be on the right track with alternator, battery.. I am thinking voltage regulator maybe possibly bad/loose grounds
 
It sounds like something may be shorting out in your wiring harness. I would inspect the harness to see if there are any obvious melted corroded wires that are creating the problem.

Electrical gremlins suck and with the upcoming trip it may be worth it to take it into John at SD Trux. He has an electrical guy that helped Brent (Brentba) trace down a problem electrical issue.
 
Had a chance to put a meter on the battery. Here are the results which i am hoping might point someone with more knowledge than myself in the right direction:

  • Not running, no lights on: 12.52v
  • Idle, no lights on: 13.4v (idle is low because ECU reset earlier), i blip the throttle for a second then voltage ups to 14.44 (approx) and stays there.
  • Turn the headlights on, voltage drops to 10v or to 9.xx give or take and at low idle, car dies
Does this provide any clues?
 
Had a chance to put a meter on the battery. Here are the results which i am hoping might point someone with more knowledge than myself in the right direction:

  • Not running, no lights on: 12.52v
  • Idle, no lights on: 13.4v (idle is low because ECU reset earlier), i blip the throttle for a second then voltage ups to 14.44 (approx) and stays there.
  • Turn the headlights on, voltage drops to 10v or to 9.xx give or take and at low idle, car dies
Does this provide any clues?




Update: Haven't started or moved the truck since the last post (a few minutes ago)...Put the meter on the battery and it read 1.2 volts! Giggled wires, nothing. Then w/o doing anything, my alarm went off and the voltage came back to 12.xx . What gives ?
 
I'm assuming you are taking the readings right on the battery terminals them selves and not the clamps. If so it sounds like an internal break in the battery.

Yes, and no....I am placing the probe in the "crack" between the terminal and the clamp. Still OK i assume.

On a side note, i just disconnected the battery and cleaned up the (2) body grounds nearest to the battery. Reconnected everything and after the truck figured out how to idle again the problem is not there. Again, this was a intermittent thing, so who knows.

Any additional insight would be greatly appreciated!
 
I have had weird things happen when there is corrosion between the battery post and the inside of the battery terminal. But you said you just disconnected the cables, so I assume you also cleaned both the post and the inside of the terminals really well? If not then I suggest it, as I have had almost the same things happen on a different vehicle from corrosion causing a bad connection.
 
I have had weird things happen when there is corrosion between the battery post and the inside of the battery terminal. But you said you just disconnected the cables, so I assume you also cleaned both the post and the inside of the terminals really well? If not then I suggest it, as I have had almost the same things happen on a different vehicle from corrosion causing a bad connection.

Yep, did that also...So far so good and i am keeping my fingers crossed.
 
What is the warranty on sears platinums? Do you have access to another battery to swap in? I would hate to be on a trip somewhere and have it diehard!
(Sorry, couldn't resist!:D)
 
The problem came back tonight on the way out of town...
Same/similar symptoms as before...I turn on the headlights, aftermarket fog lights, tap the brakes, etc while the truck is running the dash voltage meter will drop quickly then come back up. At idle with the lights off, i can tap the brakes and the meter will drop as the brake lights go on then the meter goes back to normal. if i turn "everything" on, lights, radio, then aux PIAA lights it will want to die at idle.

I cleaned up the body grounds a few weeks ago and i thought that did the trick. I did a couple hundred mile run (fwy and dirt) and all was well until tonight.

Any ideas would be appreciated.
Sean
 
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Measure the voltage RIGHT ON THE BATTERY POSTS. If it is dipping there, then the battery has some internal fault.

cheers,
george.
 
I'm assuming you are taking the readings right on the battery terminals them selves and not the clamps. If so it sounds like an internal break in the battery.

This would be were I would start. I had a similar issue years ago with my 4Runner. Turned out to be a short between the cells in the battery. It would test out as normal but a new battery solved the problem. I would go beat on Sears until they warranty the thing out and see if that solves the problem.:idea:

The other thing that comes to mind is the circuit that is run by the gauge fuse. My bro had an issue with this and it turned out to be a frayed wire in the wiring harness. My experience is second hand so I'm much help with the fix, but it's something to consider.
 
Measure the voltage RIGHT ON THE BATTERY POSTS. If it is dipping there, then the battery has some internal fault.

cheers,
george.

Thank you George. I measured last night and it was at 12.2v give or take. The odd thing last time this happened it at one point was like 1.xx for several seconds then jumped up to the correct 12.x voltage. So perhaps i have an internal issue with the battery??.....

Off to Sears later this morning.
 
This would be were I would start. I had a similar issue years ago with my 4Runner. Turned out to be a short between the cells in the battery. It would test out as normal but a new battery solved the problem. I would go beat on Sears until they warranty the thing out and see if that solves the problem.:idea:

The other thing that comes to mind is the circuit that is run by the gauge fuse. My bro had an issue with this and it turned out to be a frayed wire in the wiring harness. My experience is second hand so I'm much help with the fix, but it's something to consider.

Thanks. Hoping it is not the guage as there definatly seems to be an issue with the battery and or alternator. I placed an external meter on the battery and can see changes in voltge which seem to match up to what the interior guage is seeing....

Hopefully Sears will take care of me....
 
Sounds like a classic bad fusible link or corroded wiring between the battery and the fuse block. Check for a voltage drop on the ends of the fusible links away from the battery with the lights and engine on and off. The corrosion acts as a resistor and the more amps flowing through, the larger the voltage drop across the resistor. The voltage probably drops so low that the engine won't continue running. Look for the fusible link or any wire that runs both the engine and lights.
 
Sounds like a classic bad fusible link or corroded wiring between the battery and the fuse block. Check for a voltage drop on the ends of the fusible links away from the battery with the lights and engine on and off. The corrosion acts as a resistor and the more amps flowing through, the larger the voltage drop across the resistor. The voltage probably drops so low that the engine won't continue running. Look for the fusible link or any wire that runs both the engine and lights.

Will do, thanks.
On a side note, i see the same symptoms when i turn on the PIAA aux lights which are wired directly to the battery. Would this still point to a fusible link ?

BTW - I took the battery to NAPA and it failed their tests. I took it to Sears and of course it passed. Sears says it is only partially charged so they want to put it on a charger then test further.
 
Will do, thanks.
On a side note, i see the same symptoms when i turn on the PIAA aux lights which are wired directly to the battery. Would this still point to a fusible link ?

BTW - I took the battery to NAPA and it failed their tests. I took it to Sears and of course it passed. Sears says it is only partially charged so they want to put it on a charger then test further.

Battery tested BAD at Sears and they replaced under warranty. I realized i have only had it about 16 months, so that is not a good track record so far. Well, i will be installing it later today and hopefully that solves the problem ( for at least another 16 months).

Thank you again for those you replied with help!
Sean
 
On a side note, i see the same symptoms when i turn on the PIAA aux lights which are wired directly to the battery. Would this still point to a fusible link ?

That would certainly make it more complex. If if was just a bad battery, you would think that it wouldn't start and that once started the alternator would take over and supply enought power to run everything. Maybe it is a combination of a weak battery and a bad fusible link between the alternator and battery? The high resistance here would prevent the alternator from delivering enough power to charge the battery and keep up with demand when you turn on additional power consuming devices. It would be OK as long as power demand was low.

Symptoms of something cutting out when you turn something else on often turn out to be bad connections and fusible links are prime candidates. They are not expensive and everyone needs to carry a spare, so even if replacing it doesn't solve the problem, at least you have your spare.

Anyway the diagnosis strategy is the same: Turn everything on and look for voltage drops in the circuit starting at the battery and moving progressively away from there. When the voltage drops, there is a bad connection somewhere in between the two measurement points.
 
I have had bad batteries do this to me not long ago in my work truck ( f-450 7.3l diesel) I was driving along the freeway about 15 mins into my commute and the truck started to sputter all of a sudden, looked at the volt meter and it was speraticly all over. After about 30-40 seconds of sputteing it died while at speed. I tried to re-start and EVERY thing went dead, then 30 seconds later the dash lights radio etc came back on like someone flipped a switch, however it would not re-start. Put new batteries in it and away I went.... Still going problem free 3 months later.
 

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