Hello!

I own a Volvo v50 t5 and I recently discovered that there was a squeaking noise coming from the a/c compressor belt. I sprayed the tensioner, not the belt with wd40 and the sound changed from a squealing noise to something else but it sounded a lot better and quieter, I changed the tensioner but not the belt because it seemed to be in good condition, although when I changed the tensioner I noticed that a little piece was missing on one of the 5 grooves of the belt and the sound it was still there. I have ordered a new belt and I am waiting for it to come. Unfortunately on Saturday when I was on my way home, a red triangle appeared on the dashboard and a message, “fault in the engine electronic system” and slowly all systems, abs, airbag, power steering started to fail. I managed to take me home and tested to start the car the other day, it started normally but after a while I got the same error, battery is only 4 months old. I haven’t checked if the belt was damaged but I saw that the generator pulley was spinning along with its belt. Can it be that the a/c belt is damaged and too loose so it does not give enough rpm to the generator or the generator is damaged? Has it to do with the CEM maybe? I don’t have a multimeter but I checked the voltage of the battery with the car on using a battery charger and it was steady 11.8 V, pretty low and it didn’t go up, I don’t think that the value is reliable but I tried it until I buy a multimeter. What can it be? Any possible recommendations, solutions or similar experiences? Any feedback is highly appreciated.

thanks

regards

Vaggelis

 

A couple thoughts...

First, any time you change anything that requires removing the serpentine belt, it's a good idea to just put a new belt on. They're cheap, and that way you never end up worrying about the belt.

Second, a mechanic's stethoscope is the best tool you can buy for just a few bucks (from Harbor Freight, for example). That way when you have a squeak, squeal, knock or grunt, you can just poke around until you definitively find out what's causing the noise. It's dead simple and will save you a lot of time and money (it sure has me).

Third, I'd bet dollars to donuts that your problem is a bad alternator. When you have multiple unrelated systems failing, it's almost always because of low voltage. And yes, sub-12 volts on a running engine means your alternator is toast 99 times out of 100. Add that to your squealing and your other issues, and I'd suggest you have a new or rebuilt alternator on the way ASAP.

 

Hi habbyguy

Thank you for your answer. I checked the serpentine belt today and it was not loose so I agree with your theory about the alternator. Im going tomorrow and buy a new one, or at least a used one for now to test it.
I will keep the thread informed with eventual repairs.
thanks

 

It was the alternator, I changed it with a new one and new belts and there are no weirds noises anymore and the charging voltage is 14,54V even with the lights, the radio and the ac on. Thanks a lot for the feedback. Btw, a multimeter is always useful to have in such occasions.