atxE55K

I have read through several useful threads on this topic. Thanks to everyone who posted previously.

Last night I smelled something hot (electrical) when I got out of the car.

Three hours later I drove the car home and the AC was blowing hot air. Ten minutes later a RED message popped up - Undervoltage. Switch off consumers. Visit workshop. This was quickly replaced by Conven. Functions temporarily unavailable.

This morning I noted the following

• Car off - battery voltage is 11.75
• Car running - battery is 11.65
• Front battery was replaced 9 months / 10,000 miles ago
• Rear battery looks to be original
• Serpentine belt seems OK and alternator is spinning

Probably a bad voltage regulator, right? It is the AC blowing warm air that has me confused.


Thanks in advance for sharing your thoughts.

shardul

iTrader: (1)

check the alternator. voltage reg is easy to replace but sometimes it doesn't solve the problem and you will end up replacing the alternator

biggking

Our cars have the SBC braking system, and once voltage issues arise it begins to shut down any unnecessary auxiliary systems. A/C and parktronic ended up being cut off by my car, got both batteries warrantied out and I ended up fixing my issue.

atxE55K

That makes sense. Thanks.

Critter

9 year old battery, please tell me that it is not true. 11.V anything is a dead cell battery, forcing the alternator to try and charge this huge resistor burning out the reg or even the alternator. 05 new alternator would probably be a good idea and also change out that old battery before starting the car again, next will be the starter as it is taking a beating trying to start with low voltage.

cwmateiuc

Since you said you smelled something, sounds like the alternator to me.

You can get them redone, it's usually the diodes that burnout. Or you can just get one from a junk yard for like $100.
The alternators themselves are pretty tough, they only really go bad when some outside source causes them to (other than the voltage regulator which can wear out over time)

atxE55K

I should have said OEM, not original. I recently purchased the car and need to read through the service records, but surely the battery has been replaced at some point.

Thanks.

WoodyBang

If you smell burning the alternator is smoked.

atxE55K

You are absolutely right. I removed the voltage regulator cover with the alternator still mounted in the car and saw that some of the plastic on the back of the alternator had melted and burned.

So I pulled the alternator and took it to a shop to see if they can salvage it. I pulled the fan shroud and had to remove the S/C coolant lines and the big hose leading to the radiator where they attach to the block to get the alternator out. Not sure how people do it with those attached. I put cardboard over exposed radiator and was glad I did.

atxE55K

I took the alternator to a repair shop today and they reported that the internals were good, but the rectifier had shorted out. This is what caused the burning smell. They suggested replacing the bearings as long as the alternator was out of the car. Total cost for rectifier and bearings (part and labor) was $130. I will install a new voltage regulator (Pelican Parts) for good measure.