2003-2004 Silverado/Tahoe alternator testing - test the turn on wire

Today I go over my diagnostic procedure for testing the alternator in a 2003 Silverado which was exactly the same for my 2004 Tahoe. The most important thing is to test the turn on wire for 10.x volts with the truck running and the alternator unplugged. No turn on wire = no alternator output.

Both of these trucks also set a P1637 code. This code won't turn on the check engine light. It will set this code if there is a problem with the turn on wire circuit, or if the alternator doesn't turn on when requested.

You'll also find other fun facts in here, including how to tell if you have a 105 or 145 amp alternator, what percentage of technicians own a clamp meter, and why I don't want to listen to a torpedo heater for five hours.

Also shout outs to my former disgruntled coworkers for watching my channel, glad to hear that you guys are still mad that I'm everything that you're not.

Видео 2003-2004 Silverado/Tahoe alternator testing - test the turn on wire канала MAY03LT