When my aux pump was not working the only problem was a lack of heat at idle. Not an immediate lack, just a slow cooling off if you are just sitting idling in park. I ended up with another pump from a boneyard and it has a relay with a diode to take the load off the climate control unit so that if the pump ever goes bad it doesn't take out the CC unit. RT

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When all else fails, vote from the rooftops!
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