dash lights/ignition switch? '02 TB
kingjames1
02-11-2011, 09:17 PM
'02 TB; 120,000 miles
When I have our TB running the dash lights will come on and the guages will go to zero. Then they will go off and the guages will return to normal and back again. It acts like the key was shut off though it wasn't. The engine is still running. Now, after reading several posts here I'm thinking the ignition switch is bad. Is there a way to check the ignition switch before I buy a new one? Thanks.
When I have our TB running the dash lights will come on and the guages will go to zero. Then they will go off and the guages will return to normal and back again. It acts like the key was shut off though it wasn't. The engine is still running. Now, after reading several posts here I'm thinking the ignition switch is bad. Is there a way to check the ignition switch before I buy a new one? Thanks.
MT-2500
02-12-2011, 08:05 AM
'02 TB; 120,000 miles
When I have our TB running the dash lights will come on and the guages will go to zero. Then they will go off and the guages will return to normal and back again. It acts like the key was shut off though it wasn't. The engine is still running. Now, after reading several posts here I'm thinking the ignition switch is bad. Is there a way to check the ignition switch before I buy a new one? Thanks.
Yes.
Always test before throwing parts at it.:rofl:
Is that the only thing acting up?
First thing.
You will need a good wiring diagram and a good volt/ohm meter.
Check for proper power feeds from ign switch and fuses and wiring.
Check plugings to dash and power and ground there to.
Wilggle wires and tap test may also be needed to show where your problem is.
Lot of dash units problems around that year.
Check all TSB's pertaing to the problem.
Let us know how it goes.
Doorman and others have rebuilt dash units and some places rebuild them.
When I have our TB running the dash lights will come on and the guages will go to zero. Then they will go off and the guages will return to normal and back again. It acts like the key was shut off though it wasn't. The engine is still running. Now, after reading several posts here I'm thinking the ignition switch is bad. Is there a way to check the ignition switch before I buy a new one? Thanks.
Yes.
Always test before throwing parts at it.:rofl:
Is that the only thing acting up?
First thing.
You will need a good wiring diagram and a good volt/ohm meter.
Check for proper power feeds from ign switch and fuses and wiring.
Check plugings to dash and power and ground there to.
Wilggle wires and tap test may also be needed to show where your problem is.
Lot of dash units problems around that year.
Check all TSB's pertaing to the problem.
Let us know how it goes.
Doorman and others have rebuilt dash units and some places rebuild them.
kingjames1
02-12-2011, 06:03 PM
The only other thing was the driver's door would not lock automaticly when it is put in Drive like the other doors do. It used to but not any more. Also, the tailgate does not lock when I lock the doors.
MT-2500
02-12-2011, 06:26 PM
The only other thing was the driver's door would not lock automaticly when it is put in Drive like the other doors do. It used to but not any more. Also, the tailgate does not lock when I lock the doors.
They may be seperate problems.
Check your power and ground and plugin and wiring to dash.
Let us know how it goes.
They may be seperate problems.
Check your power and ground and plugin and wiring to dash.
Let us know how it goes.
kingjames1
02-19-2011, 04:16 PM
Alright. Went to tear into this today and the doors had locked on their own. When I went to start it it was dead. After charging the battery and getting it started it started doing something strange like there was something cycling on and off that was controlling the dash guages and radio. So before I do anymore I'm looking for any ideas of where to start. The battery charges normally at 14.7.
Here's what it is doing specifically now.The dash warning lights now stay on all the time but the guages and radio go off for about 15 seconds and come on for 5 seconds, back and forth like that. When the power comes on for those 5 seconds I can open the driver's side window, but the other windows do not work. None of the locks work anymore including the liftgate. The fuel guage also no longer comes on but the light is on indicating I am out of gas but I know there is at least a half tank in it.
Like I said, any specific place I should look at first? Could a relay cause this?
Heh heh heh.
I wrote the above about a half hour ago then decided to try a couple more things. I went out and opened the fuse boxes. I then went back and opened and closed the lift gate. Voila. Everything now works properly. All the doors lock, the windows work, the dash lights go out and the guages work correctly.
Now I'm just wondering. When I opened the fuse box under the rear seat the two test leads were draped over the plastic printed wiring. I then moved them to the side. Could that have caused this?
Here's what it is doing specifically now.The dash warning lights now stay on all the time but the guages and radio go off for about 15 seconds and come on for 5 seconds, back and forth like that. When the power comes on for those 5 seconds I can open the driver's side window, but the other windows do not work. None of the locks work anymore including the liftgate. The fuel guage also no longer comes on but the light is on indicating I am out of gas but I know there is at least a half tank in it.
Like I said, any specific place I should look at first? Could a relay cause this?
Heh heh heh.
I wrote the above about a half hour ago then decided to try a couple more things. I went out and opened the fuse boxes. I then went back and opened and closed the lift gate. Voila. Everything now works properly. All the doors lock, the windows work, the dash lights go out and the guages work correctly.
Now I'm just wondering. When I opened the fuse box under the rear seat the two test leads were draped over the plastic printed wiring. I then moved them to the side. Could that have caused this?
kingjames1
02-20-2011, 08:32 AM
OK, that's not it. It was doing it again this morning so I opened and closed the liftgate and that "fixed" it. Is there something in the liftgate that could cause this?
My wife found this elsewhere on the web. The only difference is rain does not affect mine.
HI I have an 02 Trailblazer,..I am now having some weird problems and was hoping someone might have some insight to help me on this forum.
Truck was running fine,..I use my truck for work. So I take things out of the back of my Tailgate all day long. Well it started when I opened my tail,..and I looked at the dash and I had lights on and the radio went off? Well when I slammed the tail..the lights went off on the dash and the radio came back on.
So then a day came when it started raing...thats when the all the idiot lights came on in the dash.. The car continued to run and the speedomter worked, but the power windows did not, neither did the gas gauge,oil,battery,air conditoner,power locks and back wiper. or radio. Next day the rain stopped and everything worked fine. Now its only when it rains..I lose power to everything I just mentioned but the headlights and tailights still work.
I had someone put it on a computer to get the codes, the codes go to the tailgate control module. Not the one behind the driver seat..but was told its the one in the tailgate itself.
I then had someone who had access to a Tec 2 ( GM Tool) see if it would come up with anything. They said they found the errors...but the Tool could not communicate with the Tailgate Module??My question here is has anyone had this kind of problem,..and do you think it sounds like the tailgate module is the problem....or is there somewhere else I should check before I spend the money on a brand new tailgate module??The thing that is fishy is that i was told that the body control module ( behind the drivers seat) controls some of those idiot lights,..and the tailgate module controls the others? I had the Tec 2 communicate with the body control module and it couldnt communicate with the rear tailgate...which is why I am so pluzzled? One GM Mechanic told me to put in a new ignition switch as thay have that problem all the time at the dealership..so I did...still have the problem? Anyone??
thanks in advance
-Robb
My wife found this elsewhere on the web. The only difference is rain does not affect mine.
HI I have an 02 Trailblazer,..I am now having some weird problems and was hoping someone might have some insight to help me on this forum.
Truck was running fine,..I use my truck for work. So I take things out of the back of my Tailgate all day long. Well it started when I opened my tail,..and I looked at the dash and I had lights on and the radio went off? Well when I slammed the tail..the lights went off on the dash and the radio came back on.
So then a day came when it started raing...thats when the all the idiot lights came on in the dash.. The car continued to run and the speedomter worked, but the power windows did not, neither did the gas gauge,oil,battery,air conditoner,power locks and back wiper. or radio. Next day the rain stopped and everything worked fine. Now its only when it rains..I lose power to everything I just mentioned but the headlights and tailights still work.
I had someone put it on a computer to get the codes, the codes go to the tailgate control module. Not the one behind the driver seat..but was told its the one in the tailgate itself.
I then had someone who had access to a Tec 2 ( GM Tool) see if it would come up with anything. They said they found the errors...but the Tool could not communicate with the Tailgate Module??My question here is has anyone had this kind of problem,..and do you think it sounds like the tailgate module is the problem....or is there somewhere else I should check before I spend the money on a brand new tailgate module??The thing that is fishy is that i was told that the body control module ( behind the drivers seat) controls some of those idiot lights,..and the tailgate module controls the others? I had the Tec 2 communicate with the body control module and it couldnt communicate with the rear tailgate...which is why I am so pluzzled? One GM Mechanic told me to put in a new ignition switch as thay have that problem all the time at the dealership..so I did...still have the problem? Anyone??
thanks in advance
-Robb
MT-2500
02-20-2011, 09:59 AM
OK, that's not it. It was doing it again this morning so I opened and closed the liftgate and that "fixed" it. Is there something in the liftgate that could cause this?
My wife found this elsewhere on the web. The only difference is rain does not affect mine.
HI I have an 02 Trailblazer,..I am now having some weird problems and was hoping someone might have some insight to help me on this forum.
Truck was running fine,..I use my truck for work. So I take things out of the back of my Tailgate all day long. Well it started when I opened my tail,..and I looked at the dash and I had lights on and the radio went off? Well when I slammed the tail..the lights went off on the dash and the radio came back on.
So then a day came when it started raing...thats when the all the idiot lights came on in the dash.. The car continued to run and the speedomter worked, but the power windows did not, neither did the gas gauge,oil,battery,air conditoner,power locks and back wiper. or radio. Next day the rain stopped and everything worked fine. Now its only when it rains..I lose power to everything I just mentioned but the headlights and tailights still work.
I had someone put it on a computer to get the codes, the codes go to the tailgate control module. Not the one behind the driver seat..but was told its the one in the tailgate itself.
I then had someone who had access to a Tec 2 ( GM Tool) see if it would come up with anything. They said they found the errors...but the Tool could not communicate with the Tailgate Module??My question here is has anyone had this kind of problem,..and do you think it sounds like the tailgate module is the problem....or is there somewhere else I should check before I spend the money on a brand new tailgate module??The thing that is fishy is that i was told that the body control module ( behind the drivers seat) controls some of those idiot lights,..and the tailgate module controls the others? I had the Tec 2 communicate with the body control module and it couldnt communicate with the rear tailgate...which is why I am so pluzzled? One GM Mechanic told me to put in a new ignition switch as thay have that problem all the time at the dealership..so I did...still have the problem? Anyone??
thanks in advance
-Robb
Did you not read or do post 2? :nono::rofl:
Go to post and tell us how that goes.
My wife found this elsewhere on the web. The only difference is rain does not affect mine.
HI I have an 02 Trailblazer,..I am now having some weird problems and was hoping someone might have some insight to help me on this forum.
Truck was running fine,..I use my truck for work. So I take things out of the back of my Tailgate all day long. Well it started when I opened my tail,..and I looked at the dash and I had lights on and the radio went off? Well when I slammed the tail..the lights went off on the dash and the radio came back on.
So then a day came when it started raing...thats when the all the idiot lights came on in the dash.. The car continued to run and the speedomter worked, but the power windows did not, neither did the gas gauge,oil,battery,air conditoner,power locks and back wiper. or radio. Next day the rain stopped and everything worked fine. Now its only when it rains..I lose power to everything I just mentioned but the headlights and tailights still work.
I had someone put it on a computer to get the codes, the codes go to the tailgate control module. Not the one behind the driver seat..but was told its the one in the tailgate itself.
I then had someone who had access to a Tec 2 ( GM Tool) see if it would come up with anything. They said they found the errors...but the Tool could not communicate with the Tailgate Module??My question here is has anyone had this kind of problem,..and do you think it sounds like the tailgate module is the problem....or is there somewhere else I should check before I spend the money on a brand new tailgate module??The thing that is fishy is that i was told that the body control module ( behind the drivers seat) controls some of those idiot lights,..and the tailgate module controls the others? I had the Tec 2 communicate with the body control module and it couldnt communicate with the rear tailgate...which is why I am so pluzzled? One GM Mechanic told me to put in a new ignition switch as thay have that problem all the time at the dealership..so I did...still have the problem? Anyone??
thanks in advance
-Robb
Did you not read or do post 2? :nono::rofl:
Go to post and tell us how that goes.
brcidd
02-20-2011, 10:56 AM
My buddy runs a garage- he told me he has found a couple of early built Trailblazers where the rear fuse box is not connected together properly- that the silver bolt that holds the plug underneath tight to the fuse box base was not even hand threaded- Once he tightened this connection, all electrical gremlins went away. I mention this because you were so close to the rear fuse box and probably disturbed it enough to make it work temporarily.
Check your connectors in fuse box and try to tighten them.
My buddy thinks this is from the factory- plug was installed yet never secured-- Please respond if you found another one- would be good to know that some poor factory worker ten years ago was asleep on the job- and this is the result.
I once had a 2003 Lesabre that would not communicate with ABS module- lit up tons of dash lites. Traced the problem to "no ignition" hot to ABS module-- thus no communication--found that issue to be the same type of problem- a fuse block connector not secured- not allowing power to the ABS module. Tighened fuse block connector and no more intermittent ABS lights!!
I'd say your liftgate module may have an intermittent "no power" problem - from rear fuse block connector not being secure.
Good Luck!!
Check your connectors in fuse box and try to tighten them.
My buddy thinks this is from the factory- plug was installed yet never secured-- Please respond if you found another one- would be good to know that some poor factory worker ten years ago was asleep on the job- and this is the result.
I once had a 2003 Lesabre that would not communicate with ABS module- lit up tons of dash lites. Traced the problem to "no ignition" hot to ABS module-- thus no communication--found that issue to be the same type of problem- a fuse block connector not secured- not allowing power to the ABS module. Tighened fuse block connector and no more intermittent ABS lights!!
I'd say your liftgate module may have an intermittent "no power" problem - from rear fuse block connector not being secure.
Good Luck!!
kingjames1
04-09-2011, 03:01 PM
I'm back.
The problem went a way for a while so I thought maybe the fuse box tightening did the thing. But now it's back. What I now notice is when the dash goes dead I can go to the liftgate and just unlatch it and every thing returns to normal for a while. I don't have to slam the liftgate, just unlatch it. Also, I don't know if I said this before, but the liftgate will not lock when I lock the other doors.
The problem went a way for a while so I thought maybe the fuse box tightening did the thing. But now it's back. What I now notice is when the dash goes dead I can go to the liftgate and just unlatch it and every thing returns to normal for a while. I don't have to slam the liftgate, just unlatch it. Also, I don't know if I said this before, but the liftgate will not lock when I lock the other doors.
MT-2500
04-09-2011, 03:37 PM
i'm back.
The problem went a way for a while so i thought maybe the fuse box tightening did the thing. But now it's back. What i now notice is when the dash goes dead i can go to the liftgate and just unlatch it and every thing returns to normal for a while. I don't have to slam the liftgate, just unlatch it. Also, i don't know if i said this before, but the liftgate will not lock when i lock the other doors.
as said before go to post 2 !!!!!!!!!!!
The problem went a way for a while so i thought maybe the fuse box tightening did the thing. But now it's back. What i now notice is when the dash goes dead i can go to the liftgate and just unlatch it and every thing returns to normal for a while. I don't have to slam the liftgate, just unlatch it. Also, i don't know if i said this before, but the liftgate will not lock when i lock the other doors.
as said before go to post 2 !!!!!!!!!!!
ff-racer
04-12-2011, 07:31 AM
This may not be related but near the rear fusebox you should find a slice in the carpet. I had many intermittent issues and found the cam lock had come loose on the large wiring harness. Might just take a look see.
Curlynredd
04-03-2012, 04:44 PM
I have an 2008 Trailblazer LT 4WD.
Has anyone figured out the real problem with the Trailblazer's Possessed nature. I am having the same problems with the TB not starting. Sometimes you have to have the drivers door open, and then not. Now it wont start at all. The lights on the dash come on, but Does Not start. I need help, tired of getting stranded.
Has anyone figured out the real problem with the Trailblazer's Possessed nature. I am having the same problems with the TB not starting. Sometimes you have to have the drivers door open, and then not. Now it wont start at all. The lights on the dash come on, but Does Not start. I need help, tired of getting stranded.
maxwedge
04-03-2012, 08:39 PM
No crank I assume. you need to check current to the starter relay when in the crank position, you will need a wiring diagram, it could be the switch, (maybe), this is not a one answer quickie circuits must be traced.
GMCustomerService
04-04-2012, 09:39 AM
I have an 2008 Trailblazer LT 4WD.
Has anyone figured out the real problem with the Trailblazer's Possessed nature. I am having the same problems with the TB not starting. Sometimes you have to have the drivers door open, and then not. Now it wont start at all. The lights on the dash come on, but Does Not start. I need help, tired of getting stranded.
I'm sorry to read you've been stranded by your Trailblazer! You may be looking for a DIY fix, which I respect. I just wanted to offer my assistance in any way I can (looking into recall/warranty information on your vehicle, assisting in working with a dealership). Please send a private message including the last 8 of your VIN if you would like for me to look into this further with you!
Best,
Sarah
GM Customer Service
Has anyone figured out the real problem with the Trailblazer's Possessed nature. I am having the same problems with the TB not starting. Sometimes you have to have the drivers door open, and then not. Now it wont start at all. The lights on the dash come on, but Does Not start. I need help, tired of getting stranded.
I'm sorry to read you've been stranded by your Trailblazer! You may be looking for a DIY fix, which I respect. I just wanted to offer my assistance in any way I can (looking into recall/warranty information on your vehicle, assisting in working with a dealership). Please send a private message including the last 8 of your VIN if you would like for me to look into this further with you!
Best,
Sarah
GM Customer Service
Automotive Network, Inc., Copyright ©2026