2005 Trail Blazer LS, 4.2 Engine, Auto Transmission.
Fall 2017 the Trail Blazer would not crank or start. Would not start when jumped fuse box relay. Starter tested bad. Replaced with NAPA Starter. Started properly again.
Spring 2018 the Trail Blazer starting having problems again. Would not start when jumped fuse box relay. Starter tested bad. Replaced with more expensive Rock Auto Starter. Started properly again.
Summer 2018 the Trail Blazer had occasional starting problems that slowly go worse. Changed the ignition switch and started properly again.
Starting problems started again and getting worse till wont start.
Ran the following tests
Battery 1 year old and tested good
Battery connections clean and tight
Fuse box red power wires clean and tight
No security light on
Park Neutral Switch operates normally
Fuse Box
10 Amp Fuse 17 test good with 12 volts each side
40 Amp Fuse 34 test good with 12 volts each side
Starter relay
12 volts on starter relay 86 & 87
When jump 12 volts from battery or starter relays 86 / 87 to 30 engine starts great
Used test light connected to battery + to started relay 85 and lights comes on when turn key to crank. So PCM getting start signal and going to ground.
Removed starter relay plastic top and starts great when manually activate relay.
Ignition Switch
Have power to red wire.
On crank have power to yellow wire
Replaced ignition switch with new switch and no help.
Took old ignition switch apart and looks good inside
Open the rear fuse box and 12V at the large connector with the red wire on it. Checked and it's tight
Currently when try to start dash lights dim. Hear click in engine compartment. Some times dash lights do not come back on and key is stuck in ignition like lose of power. More and more dash lights do not come back on and key is stuck. Here is the strange part when I get up off the drivers set the dash light come back on and I can remove the key till I try to start again. Seem to be associated with left side of drivers seat. When try to start and dash lights go out can press down on left side of drivers seat and dash light come back on.
Disconnected seat switches and wiring plugs that I can reach. No help. Looked at the wiring diagram and do not see a drivers seat ignition interlock safety switch that can be going bad.
Any ideas? looking at pulling drivers seat next.
Jim
Fall 2017 the Trail Blazer would not crank or start. Would not start when jumped fuse box relay. Starter tested bad. Replaced with NAPA Starter. Started properly again.
Spring 2018 the Trail Blazer starting having problems again. Would not start when jumped fuse box relay. Starter tested bad. Replaced with more expensive Rock Auto Starter. Started properly again.
Summer 2018 the Trail Blazer had occasional starting problems that slowly go worse. Changed the ignition switch and started properly again.
Starting problems started again and getting worse till wont start.
Ran the following tests
Battery 1 year old and tested good
Battery connections clean and tight
Fuse box red power wires clean and tight
No security light on
Park Neutral Switch operates normally
Fuse Box
10 Amp Fuse 17 test good with 12 volts each side
40 Amp Fuse 34 test good with 12 volts each side
Starter relay
12 volts on starter relay 86 & 87
When jump 12 volts from battery or starter relays 86 / 87 to 30 engine starts great
Used test light connected to battery + to started relay 85 and lights comes on when turn key to crank. So PCM getting start signal and going to ground.
Removed starter relay plastic top and starts great when manually activate relay.
Ignition Switch
Have power to red wire.
On crank have power to yellow wire
Replaced ignition switch with new switch and no help.
Took old ignition switch apart and looks good inside
Open the rear fuse box and 12V at the large connector with the red wire on it. Checked and it's tight
Currently when try to start dash lights dim. Hear click in engine compartment. Some times dash lights do not come back on and key is stuck in ignition like lose of power. More and more dash lights do not come back on and key is stuck. Here is the strange part when I get up off the drivers set the dash light come back on and I can remove the key till I try to start again. Seem to be associated with left side of drivers seat. When try to start and dash lights go out can press down on left side of drivers seat and dash light come back on.
Disconnected seat switches and wiring plugs that I can reach. No help. Looked at the wiring diagram and do not see a drivers seat ignition interlock safety switch that can be going bad.
Any ideas? looking at pulling drivers seat next.
Jim
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