Carrier Supra 550 "FUSE BAD"

[ChelseaNY]

Hi All,

I have 2 Carrier Supra 550's both with the same issue. The "FUSE BAD" alarm comes on immediately after hitting the on switch, also immediately after clearing code. Doesn't attempt to crank. All fuses, relays and grounds have been checked.

If anyone has any ideas or experienced this before please let me know. Thanks!!

[cadwaladr]

That alarm is triggered by low voltage,you could have various issues there is an 80amp fuse in the main relay box check voltage it should be the same as battery bbc voltage the deaths all need to be checked corrosion is common in carriers there is a connection at the starter that gives issues,start by following the connection s from the battery or you will be running round in circles!

[cadwaladr]

The spelling went crazy,basically you have a loss of voltage check all connections from the battery and the earths there are connections at the starter motor,check the power/voltage at the main fuse in the panel on the unit,best to start from the battery connections and work from there,it could be as simple as the clamps on the battery,best of luck!

[ChelseaNY]

The spelling went crazy,basically you have a loss of voltage check all connections from the battery and the earths there are connections at the starter motor,check the power/voltage at the main fuse in the panel on the unit,best to start from the battery connections and work from there,it could be as simple as the clamps on the battery,best of luck!

Thanks for the response!

Quick update.. I have proper voltage all the way from batteries through starter and alternator. having a strange issue where I'm having intermittent power loss at relay board. Batteries are at 13 volts. Getting 5-10 volts at board and sometimes will get all grounds at board including both sides of 80 amp fuse. I'm at a bit of a loss.

Thanks for all your help

[ChelseaNY]

Turns out it was a bad connection at starter. Thanks for all of your help cadwaladr!

[cadwaladr]

Ok good news,was it the same issue with both units?

[ChelseaNY]

Yes, both were starter connections. One corroded ground. The other a bad connection.

[cadwaladr]

Thanks for letting me know,I love a success !