BlackBear does GREAT work! OP was salty and quick to jumped the gun

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Fast LT1

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Well i've went round and round with the IDIOTS at blackbear performance. The pcm they shipped me had a bad fan ground and now the whole pcm is shit out. They're customer service is the absolute worst i've ever dealt with. I really can't say how displeased i am with these fools.


Is there any other reputible tuners for tahoes?
 
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Fast LT1

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Patience? It takes a week to get a response from them. They won't talk on the phone, you must email them and its like a 5 day wait for a response. Kind of ridiculous
 

RST Dana

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I have been totally satisfied with my tune via auto cal. I actually get Email responses to questions within a few minutes.
 

Justin

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I don't want to get into a pissing match by any means here, but I would like to clarify a few points. The last we have heard from this individual (until this morning) was on October 8th wherein we clarified which two PCM pins are to be used for fan control.

The email we received today contained the following text:

Both pins loose ground when 12volts applied. Basically the pcm is bad. Ground is good until power is applied.

I’ve also lost communication with my bcm. I have no power to speakers, power door locks, power windows, 4wd, fuel gauge, oil pressure gauge or temp gage.

Went through all my grounds, all were good. DLC checks out ok. Fuses good, and battery replaced. Switched back old pcm from the 5.3L and everything works. So my diagnosis is the PCM is bad.
To get to the chase, 12V power is never to be applied to the PCM pins for fan control. The PCM drives the fans by pulling the appropriate pin(s) to ground when conditions call for it. That ground trigger is to be used to energize a relay which then supplies power to the appropriate fan, fans or additional relays. Fans must *NEVER* be directly wired to the PCM. That is asking for, at best, fried circuits, at worst, an electrical fire.

We would never instruct, suggest, encourage or even permit somebody (within our ability) to apply a 12V power source to a ground trigger or wire fans directly to the PCM.
 
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Fast LT1

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I never applied 12v to the pcm, period. Thats asking for trouble. Besides the trigger wires are ground, and 12v directly to ground would result in a direct short.

In my email i meant when i apply 12v to the fan harness and tell the pcm to command cooling vans with my Verus, the ground goes from showing ground to showing open. Thus leading me to believe the pcm is bad.

So i un-hooked the fans from the pcm and manually grounded the trigger wires and applied 12v to the FAN harness, and the cooling fans work. So i know my wiring is correct and my fan harness and fans are all working correctly. Following the Factory wiring diagram for an 04 Tahoe, which i got off All Data, which is almost the exact same as you sent me, i checked my wiring and it is correct.
 

Rocket Man

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BlackBear have awesome people and have helped me tremendously over the years. I suggest working with them and if it’s urgent they will prioritize you, I know because I’ve been there and they had almost their entire crew working on my problem. But if you want to bash them, you won’t get away with that here, they’re held in extremely high regard. They’re smart folks.
 

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