Battery junction box electronics

[Asgardro]

Hi all. Inhave a constant 1.2A drain on the battery and I believe the battery junction box is at fault. I cave disconnected it fully and disassembled it. I found 2 chips on the pcb blown. Does anyone know what are those circuits from the pcb control?
I have replaced it with a new one and the drain disappeared for 1 day only to reappear next day. Disassembled it again and the same chips are blown?
It is very frustrating as I love the truck.
Thanks

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[antho]

Have any pics?

 

[Gros Ventre]

Hi all. Inhave a constant 1.2A drain on the battery and I believe the battery junction box is at fault. I cave disconnected it fully and disassembled it. I found 2 chips on the pcb blown. Does anyone know what are those circuits from the pcb control?
I have replaced it with a new one and the drain disappeared for 1 day only to reappear next day. Disassembled it again and the same chips are blown?
It is very frustrating as I love the truck.
Thanks

Need to be looking downstream of those chips. Something is overdrawing them.

 

[Asgardro]

That's what I mean.vwhat do they control?
Is very difficult to follow the pcb

 

[Darrell78]

I can't tell you what they do exactly but I would say something on the truck does not work correctly with them blown. Find what's not working right and you should be closer to your answer.

 

[Gros Ventre]

The burned component is a symptom. The problem is downstream. It's likely not a short circuit, but something overdrawing current.

 

[Gros Ventre]

Another thought: the cause may be something that cycles on & off, or is off until switched on, like headlights or sound system. Thus the burned component only burns up at certain times.

 

[Asgardro]

That is the problem. The car works fine, no problems no codes. The lights are on a switched circuit. The issue is the constant 1.2 amp draw. If I put the multimeter on voltage and measure between the negative post on battery and chassis have 12v. This means the chassis is live.
I am open to ideas

 

[Gros Ventre]

That is the problem. The car works fine, no problems no codes. The lights are on a switched circuit. The issue is the constant 1.2 amp draw. If I put the multimeter on voltage and measure between the negative post on battery and chassis have 12v. This means the chassis is live.
I am open to ideas

Do you have the rear seat aux battery? If so you have to disconnect that also, otherwise you'll still get 12VDC.

 

[Asgardro]

No I do not

 

[Gros Ventre]

No I do not

K, also if you disconnect the negative battery post cable and measure to chassis ground, you must also disconnect the positive cable. Otherwise the voltmeter simply completes the circuit.

 

[Asgardro]

Yes it makes sense.
It just puzzles me as I love the truck

 

[Darrell78]

You are not performing the draw test properly. Read up on how to do it before you drive yourself nuts with incorrect readings. The meter must be in amps and it must complete the circuit between the neg battery terminal and neg truck terminal and you must wait 45 mins before you take a reading of current draw.

 

[Asgardro]

I was not performing the draw test.
The way I discovered the 1.2a draw is connecting in series the multimeter on negative post and negative cable and also connecting jumper cable between negative post and chassis.
45 min later removed jumper and read measurement. Battery gets discharged overnight anyway.

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