So I have an issue ... My blazer has been out of comparing for almost 2 months . It's in my shop now so I'm trying to solve this issue so me and the lady don't have to share...

Ok so I have read literally hundreds of pages on here trying to solve this.

My dash lights up but none of my gauge work at all. And it will dim and light up correctly but no guages and alternator wont charge. The truck won't stay running because at the alternator (the little plug) from the ignition that tells it keys on turn on work is not getting 12v . So it just drains the battery

I checked witha multimeter .
I have checked all fuses and they are good .
I used the multimeter and checked every one of the fuses
And only 20 and 21 don't show any sort of voltage with the ignition on.

Now o know I could jerry rig this and put a wire to a 12v source and at least make m alternator charge. But I don't want to go cheap I want a working dash again and a working vehicle

I also tried the suggestion pull out cluster and if cluster is bad you should show 12v at alternator. ( we tested theory on my buddies workin blazer and he had 12v ) and I still have 0v at the alternator . Ive taken the cluster out and cleaned the contacts an put it in but there has to be somethin I'm missing

.... Please help!!!

 

What year, make, model, engine, transmission, 2 door, 4 door? Does it start and run? What terminal at the alternator does not show voltage? Do any alternator terminals show battery voltage? Is the battery good and fully charged? We need info

 

im sorry i thought my sig posted with that.. i was using blazerforum mobile

96 4x4x4 itll start and run and run till the battery dies.

i originally thought it was the alt. but got a new one and it bench tested good and have pulled it off twice and it still bench tests good. the battery is brand new been test at 3 auto parts stores all say good cells and all that jazz.
there is a plug on the back of the alternator that has one wire going into it its a very small gauge wire like 18 or 20 and its the wire that when you turn the key on it give a 12v signal to alternator to go ahead and charge basically. or atleast thats my understanding with it.

i have upgraded cables and upgraded charging cable to batt . never had issues before this stuff. im stumped and so is everyone else i know......

 

Red wire on the rear of alternator should have battery voltage at all times. The small brown wire should have battery voltage when the ignition is in the START and RUN positions only. Feed comes from fuse #4 (10 amp). Goes to charge indicator lamp through a pink wire. Out of the lamp it changes to brown and goes directly to the voltage regulator which is inside the alternator.

 

ie got no guages at all working,( the dummy lights come on when ever istart it) and ive got power at the fuses. )

i jsut am afraid to throw money at things that arent broken. It still makes me wonder if its the cluster or the ignition switch is the only thing i can come up with....

 

Do you have access to a scan tool capable of retrieving body DTC's, (Diagnostic Trouble Codes)? Body DTC's are similar to the powertrain "P" series DTC's but they start with "B". They will not illuminate the Service Engine Soon light if/when there's a problem.

 

Ooh good question. I don't know if the scan tool I have does them or not actually. .... Can you suggest any decently priced ones??

 

Scan tools that retrieve body DTC's are not generally a tool that a DIYer would have laying around. Most all of them are bi-directional, meaning they can command the PCM/BCM to operate certain functions on the vehicle rather than just see what it's doing, like a "code reader" does with the powertrain. Decent ones are pretty pricey, usually starting around $2K. Check around online, you might find a used one cheaper on eBay. Make sure it specifies that it can retrieve body DTC's and not just powertrain DTC's. Or, you could take the vehicle to a shop and have them retrieve body DTC's for under an hour of labor. If you decide to do it that way, post any DTC's that they retrieve and we can go from there.

 

Check the CLSTR fuse in the fuse panel inside the vehicle. I know on the 98's it also powers the transmission and it MIGHT power the alternator as well. The lights behind your cluster will still work but the gauges themselves wont if that fuse is blown.

It may not be your problem at all but it's worth a shot for an easy fix.

 

So thanks to captain hook my issue is resolved. I checked that fuse that gets power before cluster then cluster then power at alternator.
So fuse had power but alt didn't .. So figured I'll pull cluster and see if the connection to cluster was getting power .. I pull it off abs notice that my cluster connection is folder over.. It came off the guides and has not be letting it get a full connection.
I sure feel retarded . I buttoned it all up and have been driving back and forth to work for a week now .