Climate Control for 1987D-T
 

Blower fan will not come on when car is cold, but after 10 minutes of driving everything works fine. Anyone have this problem or know how to test climate control unit without the special M/B test unit? Thanks

In all likelihood you need to replace the blower motor itself. Before replacing it however, make sure that the bar fuse is not cracked. You will have to remove it to know for sure. Looking at it will not determine if it is cracked. I cracks along the end and will make momentary contact but is not temp sensitive. You will find it in a small black box near the master cylinder.

You can buy the motor with fans installed or save a BUNCH and buy the motor without fans. Getting the fans off your old motor intact is challenging but can be done. I use a body washer with a slot cut from the outer diameter to the center hole, slip that over the shaft and use a gear puller on that to remove the fan. Make sure the fans spin free when the motor is mounted before buttoning everything back up.

Good luck,

Make sure you put the fans on in the right direction. I don't know if they can be interchanged, but...

Good point. Remove the fans and put them on the correct end of the new motor one at a time. Changing this blower is not the biggest job that you will ever do, but it's big enough that you don't want to do it twice.

Have a great day,

I'm not sure about your particular car, but on the SL, there is a "cold engine" lockout switch that prevents the system from operating until the water temp is above something like 35C. This is to prevent cold air from blasting the occupants before the water temp gets up enough to temper the air. I would check this switch, if it exists on your car, to see if it is functioning properly. If the system fires up immediately with a warm engine, then you have your answer... which would lend credence to my suspicions...