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Blower motor fan

I have a 2001 G20 with 235,000 miles but it runs great and still looks decent. There is a problem with a short in the wiring harness the continues to short the blower motor fan. The dealer said it could be huge $s to find the short in the harness, possibly have to replace the harness etc. The A/C and heat work but can’t circulatte into the car. I live in the Northeast and have to be able to ude the windshield defroster/defogger in the winter. Is there any way to install a bloer motor fan and power from a source other than the battery? Or is there any other solution? It’s been a great car and I really can’t afford to replace. Thanks for all suggestions.

The fuse most likely ties to other things besides the blower so the trouble may not be with the blower. If the fuse blows when you turn on the blower then the blower motor may be bad. If that is what is happening then remove the connection to the motor and see if the fuse stops blowing then. If it is now ok then the motor is bad. If the fuse still blows when you turn on the blower then there is still a short on the wiring. A good tech, with a factory service manual should be able to pin down the trouble fairly quickly.

It is also possible to run a new wire between the power supply point and after the short point. This would eliminate the short. It really isn’t the right way to fix this trouble but it can be done. I just don’t like modifications like that.

Thanks - the dealer said it’s definitely a problem in the wiring harness. THere’s a short in it that causes the blower to fail they have tried to find the source of the short. I guess the problem isn’t with the blower it’s with wiring going to it. No problems with the fuses.

An alternative to replacing the wiring harness is to bypass the blower part of it. To do that, the related connections would be cut from the factory harness, and then rewired using some new wires. This is often much less expensive than replacing the whole harness. The dealers won’t do this, but many good independent mechanics will.

thank you - I’ll look into it. It’s been a great car and I hate to lose it because a mouse or someting got into the harness.

I’m sure there isn’t a problem with the fuses. The issue that I’m wondering about is since the fuse ties to other things besides just the blower, has the shop isolated those things from the power circuit and are positive the short is only on the lead to the blower motor. If they did something like removing the blower relay to verify the short is after the relay then that would prove the problem is only on the power lead to the blower.

If the short really is only on the power wire running to the blower then the simplest thing to do would be to cut the wire at each end and run another wire which would eliminate the short to ground. This would not take more than one hours time to do.

Before jumping into the wiring harness which dealers seem to love to replace based on the cost, has anyone checked the switch that turns this device on and off and operates it at different speeds? I’ll bet if you looked at a wiring diagram of this rig, you’ll find a switch located in the middle of the circuit between the fuse buss and the motor itself.
If it’s bad, it’s a a lot cheaper to fix than replacing a harness or blower. Try bypassing the switch and hot wiring the blower to see if it fires up.

Oh, and if it’s not blowing the blower circuit fuse, what makes the dealer think there’s a short rather than an open in the circuit? Shorts blow fuses, that’s what they’re for, to protect the circuit including the wiring harness.
Via con huevos.

Can someone describe what type of short (short to ground by +voltage supply too blower motor,short too B+ by ground for blower,short to incorrect voltage on either the ground or power for the motor) would damage the motor and what is the theory behind a short in the harness damaging the blower motor?

Now I can see plugging the blower motor into a 120V AC outlet damaging the motor but I just wonder here.

Myself, I think it is very presumptous to give a customer an absolute that the failure is a short in the harness, how can they be so sure?

OP has one of these inop blower motors been opened up to see exactly what failed?