Alternator...help !
no mo volvo
Joined: Oct 2010
Posts: 11,289
Likes: 109
From: 37 North on the left coast
The heater? or the heater fan ?
if the heater fan is drawing so much juice the alternator can't keep up, its possible its a bad fan motor, but its also possible there's a weak ground between the battery and alternator.
start the engine, let it idle, measure the voltage at the battery, and if you see that 12.5V, measure the voltage from the battery (-) terminal to the alternator body or ground stud. if that is more than 0.1V, the ground is bad somewhere between those two. measure the voltage from alternator ground to engine ground, and engine ground to battery (-) to see where to narrow it down.
240 fan motors are no fun to replace. it like they started with the fan motor, and built the car around it.
if the heater fan is drawing so much juice the alternator can't keep up, its possible its a bad fan motor, but its also possible there's a weak ground between the battery and alternator.
start the engine, let it idle, measure the voltage at the battery, and if you see that 12.5V, measure the voltage from the battery (-) terminal to the alternator body or ground stud. if that is more than 0.1V, the ground is bad somewhere between those two. measure the voltage from alternator ground to engine ground, and engine ground to battery (-) to see where to narrow it down.
240 fan motors are no fun to replace. it like they started with the fan motor, and built the car around it.
Thread
Thread Starter
Forum
Replies
Last Post
