Constant beeping noise check engine lights on battery light is on

SHELLIERAERIVARD

MEMBER
2000 MERCURY MARQUIS
V8
TURBO
2WD
AUTOMATIC
250,000 MILES

I have a constant beeping noise that is going on constantly and every time it beeps the temperature gauge spikes the check engine light stays on the battery light stays on even though I just put a new battery in the car. When it beeps the car acts like it's not getting any gas to the engine. It doesn't stall or anything it just it's hard to get it to go or should I say when I push on the accelerator is when it likes to beep the most.

1 Reply

AL514

MECHANIC
4,677 POSTS

Hello, it sounds like the Alternator has failed. The voltage spikes you're seeing on the Temp Gauge might be AC voltage ripple from failed diodes in the Alternator. You're going to want to get this looked at as soon as possible. It can cause the engine computer or more to fail if it is receiving ac voltage from an Alternator fault. The battery light is an indication of what's happening.
There is most likely Fault Codes stored in the engine computer as well as any other problems.

https://www.2carpros.com/articles/how-to-check-a-car-alternator

https://www.2carpros.com/articles/checking-a-service-engine-soon-or-check-engine-light-on-or-flashing

https://www.2carpros.com/articles/how-a-car-computer-works-pcm-ecm-bcm