Brake Code 4 Grounded Antilock Valve Reset Switch

[smity71]

1994 1500 350 2wd. I have my dash light flashing 3 short and 1 long when I jumper the A & H plugs. Any clues as to what the problem and fix is for this??? It comes on when I have to get on the brakes a little hard and then stays on until I shut the truck off and restart it.

Thanks for any help

[GM-Tech]

Disconnect the 4-wire connector from the brake module (near the master cylinder). Turn the key ON and measure voltage from pin C to D in the module. 0 volts, bad module. 4 volts or more, bad pressure valve. The valve is the thing those four wires go to from the module.

 

Most likely, bad valve.

[smity71]

I still need to check it but have to find my multimeter first. But, if it is the valve, where is it located on the truck? how difficault is it to replace?

Thanks

[GM-Tech]

Just follow the 4 wires mentioned from the module to the valve. You can't miss it. It's only about 4 inches away.

[smity71]

Thanks for the help. I had 4.8 volts coming out of the module. So I guess I am in to replace the valve.

Thanks

Marcus