Heater ground connection

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ChickenPinz
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Heater ground connection

Post by ChickenPinz »

In debugging a parasitic drain on the battery when the master switch is off, I found that there was a heater ground connection onto the battery relay connection with a spade-connector Y adapter. Does anyone know why this might be the design rather than a chassis ground connection? It seems like it might bypass the master switch, maybe in an effort to allow heater use with the vehicle turned off.

Is this the normal way the heater ground is connected?
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John L
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Location: Covington, Louisiana

Re: Heater ground connection

Post by John L »

I can't tell from the pics, is this the heater behind the seat or the blower motor in the front passenger cab in the footwell?
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David Dunn
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Re: Heater ground connection

Post by David Dunn »

What that circuit is for is the same as for the engine.
It maintain the ground if the battery switch is open while the heater is being operated.
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ChickenPinz
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Re: Heater ground connection

Post by ChickenPinz »

Thanks, David. Sad that it introduces a parasitic load on the battery, meaning when the main disconnect is turned off that the battery isn't truly (completely) disconnected.

And yes, the heater is off.

@John, this is the standard gasoline-powered heater that's just behind the left side front seat.
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David Dunn
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Re: Heater ground connection

Post by David Dunn »

If the heater is off and the engine is off, that relay should be open and no parasitic draw.
Look for a power drain on the positive side.
That is one thing I hated about the gas Pinzes, the negative disconnect. Basically it means that you cannot run any cables directly back to the battery on the negative side, or you defeat the cutoff purpose and create new electrical problems.

Something they corrected on the TDs and made the disconnect on the positive side.
.
The Trojan Horse... the 1st Pinz used to covertly carry troops into battle .




ATL Pinzgauer XM 718K TUM(HD) 6x6 FFR (aka The Green Grail)
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