JL Audio 1000/1 Amplifer thermistor part number??

[ssybert]

Hi Everyone,

I recently purchased a used JL 1000/1 amp on Craigslist and surprise, surprise... it ISN'T in 'perfect working order'. The red THERMAL LED comes on after a short time of use or worse, immediately on power up if the trunk is over 75F. The amp barely gets warm... I have a feeling it's the thermal protection circuit.

I've torn down the amp and found U800 snugged up tight against the heat sink between the transistors. It's a small two legged component in a metal enclosure. It has ZERO numbers or letters on it. I have no idea what it is but I assume it's a thermal resistor and likely the culprit of this false protection mode.

Does anyone know the part number of this component or a suitable replacement? I can't find any schematics of this amp and cannot find any info on this part.

Any help would be appreciated.

Thanks,
Scott

 

[ssybert]

UPDATE

UPDATE:

I tested the thermistor and it dropped to around 147k ohms holding it in my fingers. 10 minutes in the refrigerator and it read a little over 200k ohms and dropped rapidly as it warmed. It seems to be working but maybe it's drifted? Is that possible? Maybe the values at cold have drifted to a resistance expected when the amp is hot??

 

[Perry Babin]

That's about what I read across the thermal for a JL 500/1 (which likely uses the same component).