Electrical Issue Starts All Dash Lights Stay On

PeteB · Post by **PeteB** » 12 Jan 2019, 10:43

My son was driving to work and all the dash lights came on and it acted strange.
When he got to work it would not start.
After sitting for 2 hours it started and all the dash lights came on and stayed on.

We had something similar happen a few years ago, and cleaning the battery
terminals fixed it.

Since then we put in a new battery.

He cleaned them and this time it didn't fix it.

Suggestions please?

PeteB · Post by **PeteB** » 12 Jan 2019, 10:57

Seems to be fairly common with many different solutions:
https://volvoforums.com/forum/volvo-240 ... ops-38637/

Another, changed alternator and didn't fix it:
viewtopic.php?t=33091

PeteB · Post by **PeteB** » 12 Jan 2019, 11:31

I'm going to go take a look at it, but don't know much more to do that measure
the voltage, off current drain, and clean the terminals again.

PeteB · Post by **PeteB** » 12 Jan 2019, 12:58

We have AAA so my son called them and they said that the battery tested
good but that the alternator was dead. They charged the battery for him.
I measured the voltage when I got there, engine off and it was 11.8, started
it and it was 10.5, obviously not charging.
Let it run and as a last resort for the alternator, sprayed brake clean into the
sloted vent holes on the top of the alternator. Voltage jumped up to 13.9V.
I'm going to guess that the brushes are at end of life and a bit of cleaner helped
to get a connection. It is also very cold here about 30 degF so if there was
anything gummed up around the brushes it would be thicker in the cold.

Dash lights went off after AAA charged the battery.

At least we know that the problem is the alternator and most likely the brushes.

Has anyone changed the brushes with the alternator in the car, given how much
trouble it is to remove the alternator?

PeteB · Post by **PeteB** » 12 Jan 2019, 15:04

What do you know, Robert DIY has done it on the car! He calls it the voltage
regulator but it includes the brushes:

Post by **wizechatmgr** » 12 Jan 2019, 20:58

If I remember correctly the voltage regulator contains the brushes. Should be something like two bolts that hold it on. Really easy to do. The hard part is getting the alternator out - at least on my vehicle.

PeteB · Post by **PeteB** » 13 Jan 2019, 14:52

We've come to the conclusion that when the alternator is not charging and the battery
voltage is low all the dash lights come on.
He drove home from work without a problem about 4 miles.
Then today he tried to drive to my house, started the dash lights were back
on, shot the alternator again with brake clean and they went out.
Made it about 12 miles out of 15 to my house dash lights came on drove for
5 minutes more and then it went completely dead. I met him and charged it
from my car and he made it the rest of the way.
Will get the part tomorrow and hopefully put it in without removing the alternator.

Post by **scot850** » 13 Jan 2019, 16:27

What year of car is it? is it the 96 850? 99+ P80's are very sensitive to voltage related issues.

In your case the voltage/alternator would appear to be the issue, but I have also had that issue with failing ignition switch. Also worth checking the b+ cable to the main fuse box. Again more of an issue with 99+ but can affect earlier years too.

Neil.

PeteB · Post by **PeteB** » 13 Jan 2019, 16:44

It is a 1996 850.