It cut off on us at a stop light while running

JOHNBARHAM3

MEMBER
2006 VOLVO XC90
2.5L
5 CYL
TURBO
AWD
AUTOMATIC
140,000 MILES

I have a 2006 xc90. It cut off on us at a stop light while running the ac. It tried to turn over a few times after it died but very slowly and then nothing. Just a click, all the lights go out and thats it. The tow truck tried to jump the batter but we got the same results. Just a click, lights go out and nothing. Any ideas?

Ive replaced the battery, starter and checked all fuses, grounds and made sure the engine isnt locked up and all the pulleys spin freely. The two power wires that connect to the starter solenoid, only one of them has 12v, the other has 0v. Is that normal?

1 Reply

CARADIODOC

MECHANIC
33,916 POSTS

The smaller wire on the starter solenoid should not have voltage on it. When it gets 12 volts, that is what makes the solenoid engage and turn on the starter motor. What is of more importance is that larger cable. That should have 12 volts all the time, although it can be expected to drop a couple of volts during cranking. It must not drop below 9.6 volts during cranking. This sounds like the starter is having problems or the battery needs to be load tested these guides can help us fix it.

https://www.2carpros.com/articles/starter-not-working-repair

and

https://www.2carpros.com/articles/car-battery-load-test

Please run down these guides and report back.

Measure the voltage between that large terminal on the starter and a paint-free point on the engine. You'll find full battery voltage which should be 12.6 volts if it's good and fully-charged. Now measure again while a helper tries to crank the engine. If the voltage drops a lot, there is a bad connection that must be cleaned and / or tightened, or the battery has a shorted cell.