Heater blower motor up in smoke!

[EMJ]

Hello guys, so this one is easy...

The climate control for my '88 Carerra is intermittent as of Saturday with a possible short or bad blower motor. It appears the blower motor went up in smoke (literally). Symptoms:

-Smoke smell in cockpit while cruising along on highway with heater on
-Smoke coming through dashboard vents - Smelled like burned wires
-Climate control suddenly became intermittent - 1 - 3 setting worked for a while then stopped working entirely
-Car warms up when moving, but blower motor not cycling

I've had this happen in another car (Non P-car) and it was a wire harness short. Replaced wire harness, all worked well after that. Am I on the right track here? The car ran has been running well, so there doesn't appear to be any other issues.

Appreciate your help.

Thanks!

[Mysterytrain]

Remove the rear blower and test it with 12 volts. If it works thats not the problem. If is doesn't work then you have a few choices, replace the motor with the OEM unit [if available], replace the motor with a universal motor from Grainger [do a search on this fix] or run the system with out the rear blower. You would need to re-plumb the ducts and modify the engine compartment controller [pretty simple task].

Explained here:
Help! Does anyone understand the footwell blower circuit?

or here:
Carrera - Removing Engine Compartment Heater Blower

[dj393]

Wow! Same thing happened to me on Saturday! I thought my car was catching on fire!

So if I check the rear blower motor and it checks out ok, is there anything else I can check??

[imcarthur]

As Ron points out, the first thing to do is to test - to determine what fan went south. In the heating circuit, you have 3 fans. The main blower & one in each footwell. Any or all of them could be gone. Run the direct 12V test to all & report back.

All 3 depend upon the relay that is featured in the posts he linked to.

Ian

[EMJ]

Originally Posted by Mysterytrain

Remove the rear blower and test it with 12 volts. If it works thats not the problem. If is doesn't work then you have a few choices, replace the motor with the OEM unit [if available], replace the motor with a universal motor from Grainger [do a search on this fix] or run the system with out the rear blower. You would need to re-plumb the ducts and modify the engine compartment controller [pretty simple task].

Explained here:
Help! Does anyone understand the footwell blower circuit?

or here:
Carrera - Removing Engine Compartment Heater Blower

Great info. Thanks, Ron. I'll be checking today and will report back.

[Jetjockey]

If all of the fans test OK, the next place I would look is in the engine compartment fuse and relay panel. This panel is located behind the ignition coil and covered with a plastic guard that is secured to wall with wing nuts. The 16 A fuse is for Heater Blower Relay and the middle fuse (25 A) is for the heater blower. If either are melted, you should find and fix the problem that caused this (wiring or bad fan etc.) prior to putting in a new fuse. If the fuses are OK then it could be the really expensive Heater Blower Relay located above the fuses. It is the rear metal box that bolts to the side and plugs into a wire harness under the fuse panel.
There is another round relay in the trunk in position #1 for the footwell blowers. The system logic (rear Heater Blower Relay) prevents the footwell blowers from running if the engine compartment blower is not running.
Good Luck

[equality72521]

Originally Posted by Mysterytrain

Remove the rear blower and test it with 12 volts. If it works thats not the problem. If is doesn't work then you have a few choices, replace the motor with the OEM unit [if available], replace the motor with a universal motor from Grainger [do a search on this fix] or run the system with out the rear blower. You would need to re-plumb the ducts and modify the engine compartment controller [pretty simple task].

Explained here:
Help! Does anyone understand the footwell blower circuit?

or here:
Carrera - Removing Engine Compartment Heater Blower

Or have it rewound at a local motor shop. Small shops can do this for small change. I used to rewind motors ranging from fractional to several thousand HP so I'm kind of familiar with the process. This is a great solution since you keep the original motor.