'99 300TD...Fan/Blower won't come on?

[wjob]

Can't get blower, fan, defroster or AC to come on? Have checked fuses #'s 4,7, and 41 and all are good? Believe problem started when I recently had to jump the battery. AC low on refrigerant so not surprised it won't come on.

Any thoughts?

thanks,
Bill

[TMAllison]

Could be a bad blower motor regulator or bad fan brushes. The former you can verify by pulling the lower cover and nudging the squirrel cage and see if it fires up. If it does, the regulator is good and the brushes are bad.

[wjob]

Thanks for the reply. I haven't fussed with the blower, where is it and where is the lower cover? Am I correct to think that the AC won't come on if the system is low on refrigerant?

[biopete]

Originally Posted by wjob

Thanks for the reply. I haven't fussed with the blower, where is it and where is the lower cover? Am I correct to think that the AC won't come on if the system is low on refrigerant?

I think the blower is under the passenger side kick panel. If its low on refrigerant usually the EC light will not go off on the control unit in the car. You can read live data and error codes off the control unit. Google it, you will find the instructions. I'm not sure if it throws a code for the blower . But it might.

How did you jump start the car? Did you put the positive on the terminal under the hood on drivers side that is under the cover with the red + on it and the negative on the engine or intake manifold somewhere? I usually put negative on the engine hoist eye on the intake manifold.

[wjob]

Where is the control unit, do you mean the dash control and what do I google?

I jumped it using the same connections you mentioned. However, the battery was super dead since it had sat for 3 months, so I hooked my battery charger up to the spare battery I was using to jump it and turned the charger up to the start range which is 55amps. I let it build up for about 5 mins. which was enough to start it. Maybe this caused the problem with the blower? Every thing else is fine.

[TMAllison]

Blower is under the passenger side knee well. Remove beauty cover and then blower motor cover. Nudge fan with CCU on manual, not auto.

You need to pull the actual values and error codes from the CCU to diagnose the HVAC system.

Press and hold REST for 5 secs for actual values. The first 7 screens are all that's important. Screen names are posted on this site. Use AUTO up and down to toggle through them. Advance search "actual values".

Error codes you'll have to google as I can't remember the procedure or what each codes mean. Has been posted here many times too.

I rebooted most of my knowledge when the old car went bye-bye and cleared hard drive storage space.

[wjob]

Thanks Terry! I'll let you know how I do.

Bill

[biopete]

Originally Posted by wjob

Where is the control unit, do you mean the dash control and what do I google?

I jumped it using the same connections you mentioned. However, the battery was super dead since it had sat for 3 months, so I hooked my battery charger up to the spare battery I was using to jump it and turned the charger up to the start range which is 55amps. I let it build up for about 5 mins. which was enough to start it. Maybe this caused the problem with the blower? Every thing else is fine.

Yes on control unit in the car. That should be fine way to jump start it. It shouldn't have fried anything. 55 amp isn't much. My jump starter is 200 amp. Probably just a coincidence the blower went out at the same time or something.
Keep us posted.