Got warning battery/alternator on the dash every time after park in the rain. Volt meter drops bellow 12V and belt is squeaking for about 30 seconds after start. After that, car runs as normal. Is anyone having same issue? Please help.
Also, the volt meter has never shown 14V.
Thanks.

 

Yes, occasionally when it rains (or I wash the car) the belt is wet and slips. The alternator output is low -- because it is not being driven at the proper speed (along with possibly other accessory drives including the water pump) -- and the car is momentarily running off of battery power.

While you might be able to avoid leaving the car in the rain, you will have to wash the car once in awhile.

So, mind the water hose when you wash/rinse the car.

Even if you are careful, always be aware the symptom may appear anyway.

Thus when you start the engine after a rain or a wash just let the engine idle until the belt dries and spins the alternator and the battery voltage climbs to where it should be.

The temptation to rev the engine is great and it probably doesn't hurt.

Well, revving the engine of course spins the belt faster but it is slipping and then when it catches at this higher speed this can be extra and sudden stress on the belt which may (possibly) shorten its life.

Just letting the engine idle and run at its normal cold idle speed is probably best.

 

If its been a while since belt was replaced might be worth a try to change it out= could help if its worn/dried out.

 

Plus 1

The felt maybe gone from the belt.

 

Agree with others.

I never noticed the voltmeter drop nor battery warning light but have heard the brief squeaking noise after washing the car. Once dried, the noise goes away.

The last time I washed the car, I covered the engine cover vents with a shammy towel and it did a good job of keeping the engine compartment relatively dry.

 

Learn something new every day...

Never knew you could leave these out in rain.




OP, your alt may be failing. It may be that wet belts exacrbate the issues, but if it is struggling to hold 13. 13.5, 14 V when warm (and belts not slipping) you may be on the way out.

Sure, replace the belt. But keep in mind a new alt is $350 and an hours time...

A

 

I have the same issue every time I take my car to the car wash, usually when I have the AC on, so I just switch off the AC and the warning light goes away as well as the squeaking sound.

 

+2
Had the same issue a few years ago, I replaced the belt and the problem went away. There was a very noticeable difference between the new and the old belt, the old one looked stretched. The more load there is (lights, wipers, heater) the more likely it will happen.

Cheap and relatively easy to change; there's a DIY on Renntech.

 

Pretty normal on rainy days!