ok i will do my best to keep this short.
i was asked to fix this blazer up for my step sister. they said it has 99k miles on it. the cluster said that as well.
it is very clean except one spot of rust under the gas cap.

when i got it, it did not run, it had a blown intake gasket they forgot about so they over heated it and blew the head gaskets. thye also said it kept getting drained battery. (battery and alternator were new)
so i rebuilt the motor. while looking it over many nights, i found that much of the plastic up front was junk yard marked. but still looked great.

i also found that the front axle was destroyed, and they did not put the drive shaft in it. i asked my step sis, they did not know anything about it... i wish i would have checked this thing over better.
but said forget that for now. so i got it running and driving.

i let it sit over night a few times during all of this and the next day the battery was drained every time.

in testing i found that if i pulled the radio memory fuse, the battery would not drain over night, but if i left the fuse out. the entire gauge cluster, radio, and blower motor would not work at all (no power).

i noticed that the fuel gauge never moved (running or not), speedo did not work nor did the tach. when shifting from park drive ect. no light on the dash would indicate what it was in.

so i pulled the cluster found the all the idiot lights were buster off from the circuit board. the gas gauge was super glued in place. i was able to adjust the stepper motors for the other gauges and they all work except the gas gauge, that does not work still it pegs down or to the other side past full.

while leaving the gauge cluster unplugged the blazer wouldn't lose a battery charge, so i thought it was bad.
so i got one from a junk yard (with all lights inside). now all the blasted idoit lights are on all the time
(EXCEPT the check engine light that goes out after starting) ...i laughed to...
gas gauge still doesn't work.(pegs bellow empty or past full) still no indicator when its in park or not. now the security light flashes at all times. even while running.
i looked up a wire diagram to find the ground. my buddy looked for them all said he found nothing bad.

folks where in the world do i go from here. i am at a loss.

i am getting pictures tomorrow evening!!!

 

Wow, you got a real winner there. Good luck, sorry I can't be of any help as I don't know how any of that works.

 

Sounds to me like whichever computer runs those idjit lights, is blown. I'm not positive but I'd think the computer would ground the lights to turn them on as needed (the other end of the lights would be connected to the battery, I would hope through the ignition switch but maybe not since yours are staying on all the time). Have you tried pulling any codes with a scanner or reader?? That might indicate whether any of the computers are shot.

 

i have tried hooking up a couple scanners. one would lock up and not read the other gave me an error saying it couldn't connect to the vehicle. i could assume this is not good lol

 

Sell it and hope you get anywhere near what was paid for it.

Also, look up your states lemon laws.....

 

well it sucks but not much to be said on the lemon law at this point.
i triple checked every fuse in this thing, all are fine.

i also noticed when i put the new cluster in and left the fuse for the radio memory out. the battery would drain within 9 hours. so i dont think the short is with the cluster.
another fyi....at this time when the battery a was almost drained the shifter light started working for the 1st time. it hasnt sense i charged the battery.

i took this thing for a drive for about 40 miles for the 1st time.
it ran fine and surprisingly most of the lights on the dash went out. not all though.
i assume it was some sort of relearn
abs, air bag, battery, security light(sometimes flashing) and low fuel(i just filled it up)(and the fuel gauge does not work still so im guessing sending unit or a ground)
when the blazer is off the security light is on solid at all times.

my next thing is, is it possible someone swapped a bcm or pcm, or something else before i got it?
if so how do i go about checking this sense the obdii is not working? my buddy has a programmer for Chevy trucks he said he can flash the bcm if needed. i dont know if it can do a computer. but no obd is not helping.


just an fyi i wont be taking this thing to a dealer, just not worth it at this point.

 

To me, it seems to be pointing to the ignition switch/ignition switch wire harness.

As far as the ODBII port not working, maybe related to the ignition? not powering off and now allowing the scanner to communicate?

Hope you find out what the problem is!

 

is there a process i can test the ignition switch? maybe a temp bybass?

i only guessed when i unplug the 3 pin connector that goes into the key cylinder that was part of the theft system. it didnt seem to do anything. i could still start it.

also maybe someone has a wire diagram for the rdo batt fuse for this blazer?
i really want to trace this short and say deal with the rest. from what i understand its for the radio/battery. i have seen around the internet that the cluster is tied in also. i really need a diagram to try and find this short.

not sure if this is related but all of a sudden the blasted turn signals and the hazard switch dont work. i just replaced the switch it tested fine.
why is this happening, i cant do this, *cry's uncontrollably*

 

From my understanding, it's more like a 12 or MORE pin connector at the end of the steering column, under the bolster, and connects to the back/under side of the ignition switch assembly. It consists of some "smaller" gauge wires (16-18) and some heaver, high-load wires (10-12 gauge) that feed auxiliary fuse panels, blower motors, etc. and may have arced/burned together or my not make contact/connection. (Either: keeping CONSTANT contact[like your are seeing], NO contact at all)

While I HAVE NOT done this of yet, I do have a $60 harness coming from Amazon, along with the multi-function switch (constant tick from signal circuit, as you have found out also) for a new-to-me '99.

As far as the fuel gauge being in-op, that MAY be a separate, unfortunate, but well-known issue, with the fuel pump assembly. (which I'm facing now)

By the way, Is there an after-market alarm system installed?


P.J.

 

i do see what you are talking about. as for just visually inspecting it. it looks untouched. i have been sick so i haven't messed with it in the last couple days.

i think im going to pull the panels down and look at the wire harness.

there is no alarm or remote starter installed on it.

i really just want the short fixed so it stops draining. im going to dig deep tonight.