volvo low voltage alarm

depending on the alternator you have, 13.7 still sounds low when the truck is running. It ought to be 13.8, or even 14.2 with a high output.

 

Yep 13,7 is low to, 14,4 is normal charging voltage.

 

Buy a voltmeter (not many $) Test every battery invidualy buy your self. Also have someone to test the alternator, any mechanic can do that, no need for Volvo dealer

 

I have an '07 780, for the 1st few years, all I saw for voltage was 13.8. I went to a new high output alternator, and I personally checked that they had the voltage sensing wire on the correct post, and now I have 14.2-14.4. If the voltage sensing wire is on the wrong post, or if that wire is broken or corroded someplace, the regulator will only give you 13.8. But if you only see 13.7 I think you have a problem.

 

13.7 is fine for a Volvo, I max out @ 13.8, I have never seen over that. When I key off I am sitting at 13.5 giver or take .2. The overhead light drains the voltage, also the center light above the table, both I think are florescent. I understand your frustration I dealt with the same issue, but IMO disconnecting it isn't going to solve the problem, but Volvo is full of it, they can set the parameter for it with Premium Tech Tool.

 

The sad part for us Volvo owners is that we never really own the truck. We paid for them, we pay to repair them, we maintain them, but Volvo gets to decide what goes into the ecm & ecu. The dealer has to connect to central servers to change the parameter, because that's how Volvo wants it. You need to find someone that has PTT without needing a CS connection.

 

I don't mean to hijack your post, just some food for thought. I'm pretty sure in order to change parameters you also have to change the chassis ID. The only software that allows it is PTT with a connection to CS. Google Dev2tool.

 

The lights are not fluorescent, they are regular bulbs which is why they draw so much power.