Let's all learn how to debug a GAUGE fuse blown due to a short circuit

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Ordered it. Thanks for your help. I still have the replacement unit coming from cruiserparts but if I can fix this one too, I'll have a backup.
 
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Yeah, that would work fine. Overpriced, but for a single order and free shipping...

cheers,
george.
Of course it is way over priced. But I'm trading money for time. The electronics parts suppliers couldn't have it to me until late next week.
 
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I wish there was a way to get the Denso schematics and BOM so that we'd be able to repair all of these computers much easier.
 
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I do think the "27 620" markings on the TVS diode means 27V avalanche, 620W. Doing the math, this part would burn out if it had to shunt more than 24A at 27V. That's three times the capacity of the 7.5 Amp GAUGE fuse that protects the circuit. I wonder if that also means if the Amps stay under 7.5 would the part burn out at 85 Volts? I think so. :deadhorse:
 
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It'll avalanche at nominal 27V, it can't have 85V across it.... If it has 85V across it, then it has blown open circuit.

Part numbers on many parts are whatever the manufacturer decides on, so 27 620 'may be 27V 620W' or it could be just random digits pulled out of a bucket.

Just replace it and move on :)

Getting the BOM and schematics for most things is a dream, it'll happen around the same time that apple publishes that information for their products (an alternate definition of "when hell freezes over").

cheers,
george.
 
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Just replace it and move on :)

Getting the BOM and schematics for most things is a dream, it'll happen around the same time that apple publishes that information for their products (an alternate definition of "when hell freezes over").
That's the plan. Thanks for your help. It is too bad that we can't just have that information. What is it worth to anybody locked away somewhere?
 
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The replacement TVS diode arrived today and I soldered it on. The short circuit observed before is gone. I plugged it into my truck and the GAUGE fuse didn't blow and now I have A/C again. I fixed the issue finally. Thank you @george_tlc for your help in identifying the part. It was the correct part and everything works perfect again! I can't believe how much work that was and that the repair worked.
 

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