What are you using to test this control signal ? Were you on right wire ?
Blower Motor Control Processor
The blower motor control processor is an interface between the HVAC control module and the blower motor. The blower motor speed control, battery positive voltage and ground circuits enable the control processor to operate. The HVAC control module provides a pulse width modulation (PWM) signal to the control processor in order to command the blower motor speed. The processor supplies 12 volts to the blower motor through the blower motor voltage supply circuit. The control processor uses the blower motor ground as a low side control to adjust the blower motor speed.
Chevy Trailblazer EXT Blower Motor Won Turn Off The blower motor in this video don't shut off , but he show's how to test the PWM signal right !
Your blower motor control module is probably bad , or HVAC control panel is bad , or a wiring problem !
I have to ask. How long since a tune-up? Are there any applicable trouble codes?
With engine cranking, if no spark at the spark plugs and no fuel injector pulse along with no fuel pump action, have to check rpm signal.
If you have spark and fuel injector pulse but, no fuel pump action, then we check the fuel pump circuit. Did you check applicable fuse, not only check the fuse, check the fuse circuit for voltage. At the fuel pump connector, gray wire is voltage for fuel pump motor and black wire is ground.
governor is in software of vehicle either need a dealer to flash computer --lots of fleet ,rental vehicles are set with restrictor or look online, catalog ,some auto stores ,for a programmable set up-- engine management unit
Things that could be causing this
1. You have DRL main relay damaged
2. You are leaving the lights in the parking light position, not the off position.
Hi Gary:
The PVC valve will be at the engine end of a piece of tubing that connects to the air intake. Sometimes they are fitted in a rubber bushing through the rocker arm cover.
