Service Recommendations in North Phx/Scottsdale Area

[Phx Mike]

Originally Posted by vettestr

If you are willing to chase down the issue yourself page 2 of this document has a step by step, check (under voltage tests). Bet you a buck it turns out to be a loose connection and another buck it is on the negative or ground cable side.

http://www.cb4x4.com/PDFs/Electrical...%20testing.pdf

After checking connections you can (full field) alt. for a quick test to prove alt. does work or not. look here.... https://reconit.wordpress.com/2013/0...n-the-vehicle/

Thanks Jeff. I pulled the alternator out - all the connections were fine and it was not shorting against the cylinder head. It had it "tested" at the auto parts store and it "passed" although I don't have data on current vs speed/load. I replaced the regulator (connections there were good also). Checked battery connections and they were good. I have also bypassed a relay that sits between the ignition switch and regulator. Still get a slowly declining voltage the longer I drive. So - either not enough alternator output to keep up (voltage goes from 13 down to 11.5 when I have the fan on and then down from there at about 0.5 volts every 10 mins) or a grounding problem somewhere.

My schedule doesn't let me work on it full time so next stop is a shop somewhere.

Thx for all the help and will advise when it gets sorted out.

[moore_rb]

Originally Posted by Phx Mike

Still get a slowly declining voltage the longer I drive. So - either not enough alternator output to keep up (voltage goes from 13 down to 11.5 when I have the fan on and then down from there at about 0.5 volts every 10 mins) or a grounding problem somewhere.

Electric fans are notorious current-hogs, and if you drop 1.5 volts just by turning the fan on, then I think you found your culprit.

13 volts at the battery with the engine running and the fan off is still pretty anemic- Your alternator should hold rock steady at 13.5-14.5 volts with the engine idling and ALL your electric accessories running...