94 silverado electrical problems

mike holl · November 9, 2004

new to this site. i have a 94 silverado 2500 4x4. 2 days ago i started her up and she was running a little rough. went 2 blocks, put on the turn signals, the brake light on the dash came on, a buzzer went off and she was about to die. took off the turn signal and it keept running. couple more blocks and she was running fine.

last night was going down the road and noticed the speedometer was doing 85 and bouncing ( i was doing 40). i put on the lights, the brake light on the dash came on, buzzer went off, heater settings changed and she almost died. stopped at a friends for a few hours and everything was fine on the way home with lights on and heater on. this morning went to work in the dark, lights on, heater on, radio on and she ran great.

anyone have any ideas on this? i am thinking ground but dont know where to start looking. thanks for any ideas

mcreyaufmiller · November 9, 2004

Try beginning with the harness directly under the steering collumn. Follow the wires to the chasis grounds, and check for wires rubbing on moving parts.

Hope this helps.

Mike

redvett · November 9, 2004

new to this site. i have a 94 silverado 2500 4x4. 2 days ago i started her up and she was running a little rough. went 2 blocks, put on the turn signals, the brake light on the dash came on, a buzzer went off and she was about to die. took off the turn signal and it keept running. couple more blocks and she was running fine.
last night was going down the road and noticed the speedometer was doing 85 and bouncing ( i was doing 40). i put on the lights, the brake light on the dash came on, buzzer went off, heater settings changed and she almost died. stopped at a friends for a few hours and everything was fine on the way home with lights on and heater on. this morning went to work in the dark, lights on, heater on, radio on and she ran great.

anyone have any ideas on this? i am thinking ground but dont know where to start looking. thanks for any ideas

<{POST_SNAPBACK}>

Check the buss bar at the right upper on the firewall & clean the terminals and the 2 battery posts first. Check the ground cable at the engine also. Any grounds on the engine block are suspect.

mike holl · November 10, 2004

new to this site. i have a 94 silverado 2500 4x4. 2 days ago i started her up and she was running a little rough. went 2 blocks, put on the turn signals, the brake light on the dash came on, a buzzer went off and she was about to die. took off the turn signal and it keept running. couple more blocks and she was running fine.
last night was going down the road and noticed the speedometer was doing 85 and bouncing ( i was doing 40). i put on the lights, the brake light on the dash came on, buzzer went off, heater settings changed and she almost died. stopped at a friends for a few hours and everything was fine on the way home with lights on and heater on. this morning went to work in the dark, lights on, heater on, radio on and she ran great.

anyone have any ideas on this? i am thinking ground but dont know where to start looking. thanks for any ideas

<{POST_SNAPBACK}>

Check the buss bar at the right upper on the firewall & clean the terminals and the 2 battery posts first. Check the ground cable at the engine also. Any grounds on the engine block are suspect.

<{POST_SNAPBACK}>

earlier in the year i replaced the battery and put on new cable ends. checked them again and all are clean and tight. checked all grounds under the hood that i could find. traced the wireing harnes inside the cab. i am not locating the buss bar mentioned earlier. is that under the hood or in the cab. i do have a buss bar under the hood on the left side which also has the fuel pump relay and fuel pump fuse. i believe this bar is a hot junction block. i do not see a clear engine to frame or engine to body ground unless it is way in the back and i am just not seeing it. ran fine on the way to work today in the dark.

redvett · November 10, 2004

new to this site. i have a 94 silverado 2500 4x4. 2 days ago i started her up and she was running a little rough. went 2 blocks, put on the turn signals, the brake light on the dash came on, a buzzer went off and she was about to die. took off the turn signal and it keept running. couple more blocks and she was running fine.
last night was going down the road and noticed the speedometer was doing 85 and bouncing ( i was doing 40). i put on the lights, the brake light on the dash came on, buzzer went off, heater settings changed and she almost died. stopped at a friends for a few hours and everything was fine on the way home with lights on and heater on. this morning went to work in the dark, lights on, heater on, radio on and she ran great.

anyone have any ideas on this? i am thinking ground but dont know where to start looking. thanks for any ideas

<{POST_SNAPBACK}>

Check the buss bar at the right upper on the firewall & clean the terminals and the 2 battery posts first. Check the ground cable at the engine also. Any grounds on the engine block are suspect.

<{POST_SNAPBACK}>

earlier in the year i replaced the battery and put on new cable ends. checked them again and all are clean and tight. checked all grounds under the hood that i could find. traced the wireing harnes inside the cab. i am not locating the buss bar mentioned earlier. is that under the hood or in the cab. i do have a buss bar under the hood on the left side which also has the fuel pump relay and fuel pump fuse. i believe this bar is a hot junction block. i do not see a clear engine to frame or engine to body ground unless it is way in the back and i am just not seeing it. ran fine on the way to work today in the dark.

<{POST_SNAPBACK}>

First of all i hope you replaced the whole cables not just the ends. Corrosion will go right up the cable and raise the resistance. Second their is a ground coming from the neg. battery terminal going to the frame and the big one going to the engine block. On the thermostat housing their is a stud with a ground wire going to the engine harness.

On the right rear cyl head there is a ground braded strap going to the frame & a black/white that goes through the body pass through on the right side crosses the dash and goes to the convenience center on the left side. There also is a ground to the dash and should be located by the emergency brake area. If all of those are clean that should do it.

mike holl · November 10, 2004

new to this site. i have a 94 silverado 2500 4x4. 2 days ago i started her up and she was running a little rough. went 2 blocks, put on the turn signals, the brake light on the dash came on, a buzzer went off and she was about to die. took off the turn signal and it keept running. couple more blocks and she was running fine.
last night was going down the road and noticed the speedometer was doing 85 and bouncing ( i was doing 40). i put on the lights, the brake light on the dash came on, buzzer went off, heater settings changed and she almost died. stopped at a friends for a few hours and everything was fine on the way home with lights on and heater on. this morning went to work in the dark, lights on, heater on, radio on and she ran great.

anyone have any ideas on this? i am thinking ground but dont know where to start looking. thanks for any ideas

<{POST_SNAPBACK}>

Check the buss bar at the right upper on the firewall & clean the terminals and the 2 battery posts first. Check the ground cable at the engine also. Any grounds on the engine block are suspect.

<{POST_SNAPBACK}>

earlier in the year i replaced the battery and put on new cable ends. checked them again and all are clean and tight. checked all grounds under the hood that i could find. traced the wireing harnes inside the cab. i am not locating the buss bar mentioned earlier. is that under the hood or in the cab. i do have a buss bar under the hood on the left side which also has the fuel pump relay and fuel pump fuse. i believe this bar is a hot junction block. i do not see a clear engine to frame or engine to body ground unless it is way in the back and i am just not seeing it. ran fine on the way to work today in the dark.

<{POST_SNAPBACK}>

First of all i hope you replaced the whole cables not just the ends. Corrosion will go right up the cable and raise the resistance. Second their is a ground coming from the neg. battery terminal going to the frame and the big one going to the engine block. On the thermostat housing their is a stud with a ground wire going to the engine harness.

On the right rear cyl head there is a ground braded strap going to the frame & a black/white that goes through the body pass through on the right side crosses the dash and goes to the convenience center on the left side. There also is a ground to the dash and should be located by the emergency brake area. If all of those are clean that should do it.

<{POST_SNAPBACK}>

replaced the neg cable but had to put new end on the positive. could not get the cable at any parts houses. chevy dealer ordered one in but it wasnt right. their reply was "i dont know what to tell you"

anyway, i may have found it. the braided strap from the head runs to the body and another runs from the body to the frame. trouble is the two connect to the body under the condensate drain for the AC. they look rather bad so will clean up or replace. the black and white wire mentioned earlier is connected at the thermostat housing along with another ground. i have yet to find the dash ground near the parking brake. trailer brake package was added and its a mess. did find a black wire in that area cut so must check that out. thanks for all the ideas and i hope the braid was the problem. only time will tell. if not i will be asking again. thanks

Rookie · November 11, 2004

If you have a tilt steerinbg wheel and use it a lot i have seen the harness wear and crack. I had a 90 chevy that the light would not work sometime and unless the wheel was left in the up position it would not run and funky things would happen with the gauges. it was a pain to replace, so i went to the bone ward got an entire colume and reoplaced it that way it was plug and play problem fixed.

Wingnut · November 11, 2004

Another vote for the battery cable.

redvett · November 11, 2004

[quote=mike holl,

trailer brake package was added and its a mess. did find a black wire in that area cut so must check that out.

Mike by all means make sure the ground for the dash is good. Check at the ALDL where it attaches to the IP frame there may be a ground there instead of at the e-brake.