Last post on Nov 05, 2013 at 7:31 AM
You are in the Chevrolet Blazer
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Chevrolet, GMC Jimmy, SUV
#462 of 609 Re: Underhood fuse box on 97 Jimmy [slarra]
Nov 15, 2009 (5:17 pm)
I also have a 1997 GMC Jimmy SLE. There is no fuse or relay box under the hood
of mine either. There is a big black box under the hood on the right side.It is your
PCM (powertrain control module) or computer is what some call it. On the firewall
behind the engine there are three relays.All three of these are for the airconditioner
unit.The box on top of the left (drivers side) fender is the anti lock braking system.
There are three relays behind the glove box. One is the fuel pump relay, one is
for the headlamps for high and low beam and daytime running lamps. The other I
can't remember just now. When you open the drivers door, on the side of the dash
is where the fuse box is located. There are two relays in there also.So, no you are
not an idiot.
#463 of 609 strange electrical indications and problems 99 jimmy
Nov 16, 2009 (11:18 am)
I was driving down the road today at about 70 with the cruise control on and the battery light came on, a very sort while after, the airbag light came on. I looked down and the volt meter was droping. At about 9 to 10 volts the gauges died. (All except oil press and the transmission indicator as well as milage.) A mile or two down the road the truck was slowing (loss of power) so I pulled over to the side of the road to squeeze as many miles out of it as I could. I hit the edge of the road at about 50 mph and everything came back to life. Cut the hunting trip short turned around and on the way home it did the same thing another 9 times for the next 30 miles to the house. There may have been some viabration when I pulled over hitting the rumble strips but I would hope that we don't jump on it and assume a bad ground right off the bat. Checked the battery under load reading 12.4v stuck the meter on it after starting the engine and was reading 14.06v then it would jump around abit to 9.05v, 10.0v, 12.4v then back up to 14.06v and hold steady. The battery is old but the alternator is 8 weeks old. I have been reading the posts and found some similar but not the same. I also have been dealing with the inaccurate fuel gauge for about 3 years. I fill the truck up indicates full, never gets below half a tank until it jumps to E. Fluctuates when shifting from P to D or R. Love this truck but don't trust it to take trips with any more. I have had it since new in 99. By the way it is an SLE 4x4 4.3L v6. Appreciate any input anyone might have. Thanks.
#464 of 609 Re: strange electrical indications and problems 99 jimmy [cwangs1]
Nov 16, 2009 (2:05 pm)
The first and formost thing I think of after reading your problem on the Jimmy is you may have put a rebuilt alternator on it. I have a 1997 Jimmy and had to take my wife to a specialized hospital about 200 miles away. A week before we left,I had a
bad experiance very simular to yours. After checking and letting the parts store check it, it was bad. When it started going bad, it would lose power and I had to
pull off at several rest areas because the lamps were getting dim and the doors locked by themselves and a couple other wierd things happend also.I would sit in the rain and finally get someone to jump me.When it started the guage would go up to normal as it rapidly charged the battery. It happened a couple more times that night. Altinator was the first thing I thought of.As I said it checked bad. I bought a reman altinator saving a great deal of money. It was good until the trip home from the hospital,same thing. I will also mention our 99 grandprix gt did the same thing only we could'nt get the windows to work at all.We were stuck inside
and I had put a reman on it too.Put a new(not remanufactured) one on both vehicles
and that's been a few years back.My sons 99 camaro he put four remans on it before he finnaly listened and went to new. I don't know if you went for reman or new but,new ones go bad sometimes too. It shorted out the battery in my Jimmy also.Had to get a new one. Check or have your altinater checked first
#465 of 609 Re: strange electrical indications and problems 99 jimmy [cardoc50]
Nov 16, 2009 (3:19 pm)
Thanks, thats what I initially thought too. I guess I will pull it and have it tested, it's not that hard to do. I have a couple minutes tonight and tomorrow night to do it.
#466 of 609 Re: strange electrical indications and problems 99 jimmy [cwangs1]
Nov 17, 2009 (4:51 pm)
Follow on to what cardoc said above, you may have a battery plate (internal) that is coming apart. Will short, put a big load on the alternator, then when you hit the rumble strips, vibration knocks it free. Cheap easy way to know if this is happening is to feel the battery cables when you see the voltage drop on your meter. If those puppies are getting hot, the alternator is cranking amps, and the battery is sucking it down.
All that being said, your "new" alternator may be having issues. Cruising on the road in daylight hours with the fan on low, you are not putting much stress on the alternator at all.
By the way, that gas gauge problem you are seeing is a software issue with '99-'02 GM trucks. Instead of buffering the gas slosh in the tank with a baffle, the designers used software to "average" the signal coming from the sending unit to the BCM. Problem is, some code junkie only conditioned the signal when the vehicle is in drive, not reverse, or park. Want to see something cool? If you back out and the gauge drops and turns on the "low fuel" lamp, put the vehicle in drive and get moving up to about 20mph or so. Shift the tranny into neutral and put on the brakes. The fuel gauge will swing back up to the true reading. Before you stop, shift back to drive. This kicks the software back into "averaging" mode and the gauge will behave normally.
You don't want to know how long it took me to figure out what was causing this!
#467 of 609 Bad ABS Module?
Nov 17, 2009 (5:44 pm)
I have a 1999 Chevy Blazer, about 157,000 miles
Like clockwork after 30 minutes, the abs will kick in under light pressure and the abs light will come on and stay on. After turning off the car for while it turns off then will repeat.
Both the wheel hubs and sensors are new, the rear one is not but I cleaned them all just to double check. Did not see any issues with worn wires. The problem started months after I replaced the wheel hubs.
I have only had the blazer since the spring and would notice the pedal would chatter a little when backing down my drive way which is a slight incline. Thought it was due to rear wheel bearings which I have not attempted to replace yet.
Looking online found you can get the module rebuilt. Before I attempt to take this out was looking for other options.
#468 of 609 Re: Bad ABS Module? [dp2226]
Nov 17, 2009 (8:09 pm)
I can only tell you what I had to do. Tighten the rear shoes just enough to touch
the drum. not drag or hold back. Bleed the entire brake system starting with the
right rear (farest away) and work your way up to finish at left front. Try it then and see what you have. It should be ok. If not bleed the module. I do not know where you start there or the exact procedure. I may have it in some of my manuals but,
you probably have one or have access to one. I know when your rear shoes need
replaced or tightened That brake pedal and the noise the antilock module makes
sounds like the blazer's falling apart. It's funny to me when mine has done it over
the years.You don't need rear wheel bearings unless you see dark moist thick
oil caked on the inside of the rear wheels.When a bearing goes out the seals
warn you first.Just try the rear shoe adjusting and bleeding first and you will be
surprised. That antilock brake system GM came out with is a joke.Every GM
vehicle with that system should be recalled for a less complicated normal system.
Sorry I said it's funny to me but I know how you feel. Good luck pal.
#469 of 609 Re: Bad ABS Module? [cardoc50]
Nov 18, 2009 (5:51 am)
Sounds good and I will give it a try. I did have a new master cylinder put on in the summer and rear calipers. Maybe there is some air left over or something.
Does it matter if I have disc brakes vs drum brakes? I hate the aluminum calipers, stripped the bleeder on the first set just putting them on.
Did your blazer do it after driving for almost the same amount of time?
Thanks for the tip on the rear wheel bearings, back end sounded a little loud to me. The seals are definitely not leaking. Guess I am paranoid after finding out the first cause of a loud ride was the u-joints.
#470 of 609 Re: Bad ABS Module? [dp2226]
Nov 18, 2009 (6:33 am)
I was'nt aware you had rear discs.As far as mine,like I said when the rear shoes got thin it would do it. Generally a car will go through 2-3 pairs of front pads to one set of rear shoes. Disc brakes really set themselves because as the pads get thin
the piston in the caliper goes further and further out with no slack between the piston and brake pad. I like aluminum calipers on motorcycles and ATV;s but on
a vehicle like ours,no way. I suggest you quickly crack the bleeders and close them
immediatly(to see if they are going to loosen or strip)Now comes the fun.Bleed the system from rear to front. Oh yea, if your calipers are corroded,the piston may stick
and the pads will chatter if they are just lying there unassisted and there goes your light and antilock noise.Check the calipers repair or replace as needed. Bleed the
heck out of your brakes starting at the farthest away working forward.Your last one
should be left(drivers side) front.I think you'll find this to work.If not,have your under
hood antilock module checked.It has a printed curcuit board that can easily be replaced too.I would leave that one to someone else after getting bleeding instructions first. Good luck.P.S.Wanna buy a used Jimmy? LOL.I feel you'll get
it this time around. Good luck pal.
#471 of 609 Re: Bad ABS Module? [cardoc50]
Nov 18, 2009 (3:14 pm)
Definitely will give it a go. The front calipers are old so will check them out.
I just popped the abs module out and unfortunately it is a Hayes 310 which according to a couple sites it cannot be rebuilt