New member, first time user.

Any insight at all is appreciated.

2001 Blazer 4x4, 170 thousand kms

Lost power to dome light, Glove box light, power doors,and radio(although lights for the radio are on). RPM guage,speedometer and odometer not working. When turning the key only warning light that comes on is the Engine light, nothing else on startup. Starts up easily, first try as normal.
Very sluggish and hesitating taking off but after 50 km/hr seems fine. All this happened all at once.

check all fuses inside and under the hood and all seem good.

Help.

 

Wow, I think there are four main plugs to the pcm. I would dissconect the - from batt then un-plug and re-plug the four to the computer then reconnect the batt. See were that gets you.

 

Did as you suggested...no change.

Today something else happened..
Turned off the key and took it out and it continued to run.
Ran for about 2 or 3 minutes than turned off on its own.
Doesn't happen every time but twice today.
Could all these things have something to do with the ignition switch?
Seems to be a lot of things to be tied to the switch.

Oh and on top of all this, just noticed today that the 4x4 switch is not working either.

Any insight?

thanks

 

Do you have any aftermarket starters or alarms on this baby, they hook up through the ignition switch. The module may have fried. It sure seems like some kind of IC fail. The switch is mostly mechanical and mine showed sighns of going before it went.

Anyone else???

 

I have an aftermarket starter on it...over a year ago with no problems.
I do have some problems with the key not always turning easily...takes a little jiggling
some times to turn. I can actually pull the key out now without turning it off.

should start there at the switch I guess.

 

Could very well be the ignition switch. This link should help with diagnosis. Kind of expensive to replace it on a guess

https://blazerforum.com/forum/articl...-switch-33465/


It's difficult enough to diagnose electrical problems, and when they're intermittent, it gets even more difficult. Start by checking voltage at the various fuses affected by the switch when it's in the RUN position, make sure they all have voltage, on both sides of each fuse. The diagrams in the link will help.

 

That's a cylinder or interlock problem, the key thing. Next thing I would do is find that aftermarket starter module and unplug all. This sould cause no extra problems as the wires are just spliced in to your main stuff and will just leave them open.

 

Update

Turns out that my electrical problems are related to the Headlight switch.
When I turn on the lights manually all power is restored to the guages, radio, power door locks, dome light and 4x4 switch.
But...when I put the dome light on everything dies out again...not right away but within a minute or so. Turn the dome light off and everything is restored as long as the lights are manually turned on.

So my question to anyone out there...is this the switch or the the automatic headlight sensor?

Appreciate any input at all.
Thanks

 

I'm having the exact same issues that you describe. I believe at least on my 01 that it's the multifunction switch that's causing all the trouble. I say this because i am certain that there's a circuit that ties in with the headlights.

 

Turns out my main problem with the electrical issues was with a corroded wire under the fuse box in the engine compartment. It fixed all of the issues I had except for the Brake Lights. I still only have the center mount third brake light.
Obviously a whole other problem which I have yet to look into.

I was quite surprised to find that ONE wire could cause such havoc to the electrical system.

I want to thank everyone on this forum, could not have ever found it myself if it wasn,t for ALL the posts I have read in the last few months.
This is a great site...very helpful.

If anyone has any ideas about my brake light problem...I would love to hear it.