I am trying to debug several issues with my 2004.5 S40. When doing this, I measure 11.5V at the fuse box under glove box on the passenger side. Where are the ground locations that I should check? Or other connections between the battery and the fuse box that I should check?

Thanks!

 

Not nearly enough info for anyone to give you a single answer.

First, what's the voltage directly at the battery? If it's the same, you've found your problem (bad battery).

Secondly, is that voltage with the car running?

 

@habbyguy Thanks for the help. I finally had a chance to get back to this. Voltage at battery is `14.5. Voltage at fuse box under glove compartment is now showing 13.9V, which should be fine.

However, I am still getting a P0091 code - "Fuel Pressure Regulator 1 Control Circuit Low". Car seems to be running great, and I have already changed out the fuel pressure sensor.

Any thoughts? Ideas?