I have an 86, when I bought everything worked. Went on a trip had a battery issue replaced the battery. Now the power seats,cruise and power doors don’t work. They are all on the same circuit breaker. I checked it and it gets hot and then trips. I am told it’s prob a ground issue. Which ground works this circuit? Any ideas?? Everything else works and I check the ground strap from the block.

 

there are lots of ground locations on a c4.....does everything work until the breaker flips???...you're not blowing fuses?....no codes?.....you'll need a fsm to find the grounds and the wiring diagram....disconnect all effective circuits and plug them back in one at a time to see where the problem is.....good luck... my door locks occasionally stop working....someone here told me to turn the headlight switch to "dome' and off....magically, they work!!!!

 

Hello there Traumanuts,

I would start at your battery and work back from there. The battery connections have got to be as clean and functional as possible. I would start by wiping it down and then use a wire brush to clean the posts and get both surfaces nice and shiny. Once the connectors are clean re install them and be sure the connection is tight. Be sure that the battery is fully charged and ready for usage before connecting it to the load. The Corvette needs 12 volts with access to a lot of current so you need a good functional battery.

You might even want to test the circuit to see if the Relay is defective, they can and do fail. I recommend most people to start at the actual battery itself. Measure the battery voltage and then measure it at fuse block. If there is a difference it is likely where the fusible links are powered. On my 1988 C4 Coupe the post is under the side cover over the rear of the battery. The post is mounted on a frame rail and this is where 7 different Fusible Links and their circuits get powered. Sometimes the fuses need to have their surfaces wiped clean every now and then

One of my favorite tools for working on Cars is something called the "Power Probe". I have version 3 and 4 as I use them a lot. This tool connects to your battery and allows you to power or supply battery ground to the tip of the probe. Using a rocker switch you can turn it on and off allowing you to apply battery voltage or ground by simply pushing one side or another of the rocker switch. I have found so many uses for this tool. The newer #4 version can show the voltage kickback after a relay is energized in a graphical format. This is one useful tool especially for Corvettes with their ground issues every now and then.

 

Check the wires under the seats to see if one is pincher or caught in the tracks.

 

There is a meter available I got at HF that can be plugged into the fuse block (You will have to make jumpers to use against the circuit breakers) and show how much current is going through any fuse or circuit breaker. In my case I found the wife had put a lipstick tube in the well by the seat adjuster and was being pressed against the switch by other stuff piled on it. It helped my track down my issue. Remember that the interior light relay stays energized for a while after the door plunger is depressed so take that into account while waiting for the meter to settle in when testing the interior light circuit.