1991 Accord SE

3 mos. ago the Voltage started dropping down to 12-13V (according to gauge) when I step on the brakes - esp. when there are other electrical loads like blower, A/C, headlights, defroster etc. Sometimes it will go below 12V. - it only happens when I hit the brakes- esp. when I'm stopped at a light which means the engine is almost idling and the brakes are applied. The car almost wants to quit sometimes while at a light.

I have a feeling there must be something shorting in the brake circuit.

I'm going to check the whole circuit for a Voltage drop but if someone has experience with this particular problem it might help make the job quicker.

Anyone come across this problem?

Matt B.

 

A short would draw a lot of current and the fuse for that circuit would pop. I suspect your alternator is not putting out enough juice, your battery is nearing the end of it's life, or the electronic load detector isn't working properly.

Measure the battery voltage with the engine off to get a base line reading. It should be at least 12 volts, and preferably more. Then measure at idle. If the alternator is working, the voltage should be higher.

 

Hi I have a 2012 civic lx with a high output alternator and my only issue is when I applied the brakes the voltage would do down when coming to a stop but after I accelerate it goes back up to normal