1999 GMC Sierra - Page 3 - Answered Questions & Fixed issues

I would think so, if the security light is on the computer is not registering the key, try turning the ignition to the "on" position for 15 minutes and see of the security light goes out and then see if it will start.

Two things to try 1. in the underhood fuse block pull the B/U LP fuse. do the lights go out? 2. in the underhood fuse block remove the VEH B/U fuse. Do the lights go out? Let me know what you find. This will help determine what part of the circuit the problem is in and narrow things down a bit. I’m happy to assist further over the phone at https://www.6ya.com/expert/jeremy_d728a59f986299fa

fault in the wiring running up the steering column i would presume and look here first

For what?

Run your VIN # at a dealers parts counter Turn the rear tires around 1 time & count the turns on the driveshaft My old S10 blazer has the build sheet in the back of the glove box Your B Pillar label can be decoded somehow also, if you had the factory manuals,usually in the first couple pages of the manual The front will not be an exact match to the rear with 4x4 Usually a different manufacturer on the axles & gears

Another noisy producer might be the scanner motor....

Check other players to see if plays on any player. I had a computer once that kept defaulting to "data CD" no matter what I was burning, so I had to manually go to the setting and set it for "music".

It could be many things.... I will start to look at O2 sensor heater.... if you have a scanner to read data. Don't start engine the voltage should be around 450mv key on wait 3 to 5 minutes....the O2 sensor voltage should raise toward 900mv. if it doesn't then bad heater detected. what else ...is gaz, Map sensor ,Maf sensor,tps sensor,temp sensor, hope it helps

You will likely need to replace the fuel pump inside the fuel tank.

check oil brake level. or disconnect switch wire at master cylinder hope it helps

it looks like a tcc (torque converter clutch)circuit problems or torque converter clutch itself hope it helps

Is your shift linkage all connected maybe reset your range sensor/neutral safety sensor

Not sure what you are asking

That's a random misfire. It could be bad plugs, wires, coils, intake gaskets and a whole lot of other things. You need to have that diagnosed by a mechanic. The cause of my po300 code was a bad intake gasket found by the random misfire of cylinders 1 and 2 so it was at the front of the vehicle the mechanic spayed something around the front of the intake and the rpm's increased. bad gasket sucking to much air into those cylinders and causing a false misfire. I say false cause it did fire the gasses produced where not right the computer did not like the extra air

Code 300 is for a random miss and may be tough to track down. You may have to wait until one or more cylinders are not producing power.

look for a harness unhooked under the driver side dash

Usually a faulty blend door under the dash.

have a professional steering shop look at it and adjust the rack /box if there is no faults.

Instead of that, see if you can get an electronic flasher unit for your vehicle that does not depend on the turn signal light load (amps) to control flashing speed. This is much simpler than splicing things into wires.

Are you saying you don't have blower at all? Defrost, floor and panel are the only three separate modes you have. If it's not blowing at all and the fuses are good, check the wiring behind the glove box. There's a two wire plug with a large red wire just about center of the glove box opening that's known for burning out. If it is you'll see the burned spot on the connector or wont be able to disconnect it.