I just got my 07 Outie back from the dealer. I brought it in because the lights a dimming very badly when the AC turns on. I checked the voltage and it will go from 14.4 with high beams, fan, radio, domelights on. When I turn the AC on it drops to 13.3v. If it is at idle, it will fall to around 12v. The biggest problem I am having is that when I am driving at night the head lights will dim when the AC compressor turns on. The dealership told me that is normal. That is wrong. They wanted me to let the tech take my car home with him at night to see it dim the lights.
Has anyone else had this problem? If so, did a dealership fix it, and how?
Thanks for any help.

 

Morons - it is not normal not by a long shot. You definitely havea problem with the charging system- I just ran the following voltage readings for comparison:

Idle - Radio on, highbeams on, A/C on full 13.9 to 14.1 volts

60 km/hr / 6th gear - same conditions - 14.2 to 14.4 volts

100 km/hr / 6th gear - same conditions - 14.4 to 14.5 volts

 

If it only happens when the AC kicks on, and not with a high electrical load occuring by having other things running(ie. voltage staysgood with lights on, heater blower on high, radio going while the vehicle is idling), chances are good that there is a short in the AC compressor clutch or wiring.
Here's a test to try:
- find the wiring going to the compressor clutch. It is near the pully on the end of the compressor. It allows the compressor to either freewheel or link up to the belt that runs the accessories. Disconnect the wiring. If it can't be disconnected directly at the compressor, follow the wiring back until you find a connector.
-create the condition that was showing the problem previously. If the lights no longer dim, you've found the culprit. If the problem continues, you may have a short in the wiring(possible, but not too likely), or there may be a relay that controls the clutch. Check your manual for fuses or relay locations and see if there is one for the AC compressor. Pull the fuse or relay and you're closer to a solution if the problem clears up. Let the tech doing the repair know what you've found. Let us know as well.

 

I called the dealership today, they said that they were going to call the Mitsu Tech line. The had not done it yet, and since that was over 5 hours agao, I still haven't heard anything, I assume they never called. If this was one of my older cars, that is out of warranty, I would start to do some deep troubleshooting. This is only 6 mo old, and I don't want them trying to blame me for anything that is wrong, ie throwing a code. I think that it is one of two items: either the ac clutch or the coolant fan. I think it is the fan because I notice that the copressor kicks in a millisecond before the fan comes on, and that is when the lights dim. I was told by the dealership, that it woul throw a code if I disconected the fan.
I think it is sad that they spent all day to tell me that the lights are supposed to dim when the AC comes on. This place has just about lost my confidence.

 

of course its normal. An alternator at idle can only produce about 20-30 percent of its maximum output.
its normal on just about all cars on the planet. When you have a full electrical load running at idle, you're pulling maybe 40-50 amps. the output of the alternator is not going to be sufficient until lightly revved.

 

That is not the problem. The problem is that when I am driving, when the AC compressor is engaged the voltage will drop at least 1 volt or more.

 

Likely an alternator (or circuit) problem. And no, it is not normal, and no, not every car does that. In fact every car should not do that. The alternator should keep the battery above 13.5V any time the car is running regardless or engine rpms period. Ashort in the AC compressor is not going to lower the voltage at the battery, it doesn't work like that. A short would most likely blow the fuse anyway. AC is a LARGE electircal draw on the engine, so it makes since that you notice the lights dimming with the AC on if there is a charging output problem.

 

I would check the alternator first. If there was a loose wire you would notice it all the time. Im betting on its dieing or just a bad alt that cant handle the load.

 

So, I guess that no one else is having this problem? I talked to the dealership last evening and they said that Mitsus tech line has had complaints from other dealerships, but they say that it is a not occurance. I told the guy that I must have abought a bad car, because it did not do thid when I bought it, it just started. So, it was obviously broken when it was new! He had no comment. Well, I have opened a case with Mitsu, we will see where that goes.

 

I would get them to swap alternators and see if that cures it.At least rule it in or out as source of problem.