Help! Idle rough lights flicker, smoke?
- Thread starter Martinco
- Start date
JTee2017
Well-known member
Check and clean battery connections cables at both the battery and at ground points under the hood and engine block.
Also. . . what year car . . model . . .. engine .. .. etc. Helps others to help you.
You already posted this . . why another thread? Did you check this stuff already? Some feedback would help also so it doesn't get repeated like now. ..
.
Also. . . what year car . . model . . .. engine .. .. etc. Helps others to help you.
You already posted this . . why another thread? Did you check this stuff already? Some feedback would help also so it doesn't get repeated like now. ..
.
JTee2017
Well-known member
Alternator IS a possibility but so is the BCM (though not likely).
If the regulator in the alternator has gone flakey, it can set charging voltage too high. +15.2 volts or so should be the highest you see and only for awhile and it should change.
Here's the thing. On these newer cars, if you let a battery go to long and it gets a dead cell (low <10VDC ) , The Alternator is instructed by the BCM/ECM to raise the charging voltage to try and compensate. If left to go on too long, it will damage the regulator in the Alternator. This usually results in the Alternator "stuck" in high charge >15VDC mode.
So an owner replaces the battery finally, and later, now the Alternator still is stuck in high charge > 15VDC mode. This can damage both the new battery and other things in the car.
Note . . the Alternator may not always be stuck in high charge mode but go in and out repeatedly.
You can buy a small auxiliary power socket Volt meter to monitor voltage.
https://www.amazon.com/s?k=cigarett...hter+volt,electronics,207&ref=nb_sb_ss_i_1_22
If the regulator in the alternator has gone flakey, it can set charging voltage too high. +15.2 volts or so should be the highest you see and only for awhile and it should change.
Here's the thing. On these newer cars, if you let a battery go to long and it gets a dead cell (low <10VDC ) , The Alternator is instructed by the BCM/ECM to raise the charging voltage to try and compensate. If left to go on too long, it will damage the regulator in the Alternator. This usually results in the Alternator "stuck" in high charge >15VDC mode.
So an owner replaces the battery finally, and later, now the Alternator still is stuck in high charge > 15VDC mode. This can damage both the new battery and other things in the car.
Note . . the Alternator may not always be stuck in high charge mode but go in and out repeatedly.
You can buy a small auxiliary power socket Volt meter to monitor voltage.
https://www.amazon.com/s?k=cigarett...hter+volt,electronics,207&ref=nb_sb_ss_i_1_22