KWR

Turn the key and these lights are on

I have a 93 Z28 that sat for 7yrs in storage.
Turn the key, no fuel pump prime, no security light and no crank. New battery, checked fuses, cleaned ground, I have the original keys.
Any help would be greatly appreciated!

Injuneer

May be an issue of the theft deterrent module (TDM) not receiving power from the ignition switch. The TDM controls the “SECURITY” light, and provides a ground to the theft deterrent relay (TDR) to permit starter cranking. The “SECURITY” light should come on in “BULB TEST”. If you don't have a copy of the 1993 factory service manual you can download (free) a copy here:

https://www.mediafire.com/?40mfgeoe4ctti

I would have to look at the 93 fuel pump schematic to see if there is any circuit from the ignition switch that supplies the three non-functional components. I'll try to take a look in the morning.

KWR

I was looking for the fuel pump prime wire and only found a small gray wire and connector sticking out of the harness by the back right side. I'll download the print now.
Thanks!

Injuneer

That would be it.

Shoebox site has a lot of detailed info on the 93-97 LT1. A great reference.

4th Gen LT1 F-Body Tech Aids

http://shbox.com/1/fuel_pump_prime.jpg

GaryDoug

Post a photo.

KWR

Is that prime wire?

KWR

Where should I start on this?

Injuneer

Appears to match the photo I linked in post #4.

The prime connector bypasses the fuel pump relay. You are basically verifying whether the fuel pump is functional.

Run a 14 ga (or heavier) wire from the red plastic positive distribution box (on the passenger side inner fender, near the battery) to the fuel pump prime connector. When you apply 12 volts to the connector, the pump should turn on and be audible.

If the fuel pump is functional, you have to look at the wiring from fuse #5 in the end of dash panel to the fuel pump relay, and to what in 1993 was called the "PASS-Key II Decoder Module". They are both supplied by fuse #5. The fuse appears to be OK, since that fuse also powers the ECM,, and your dash shows a "Check Engine" light.

Fuse 5 schematic is on page 8A-11-4 of the FSM.

Fuel pump schematic is on page 8A-21-5

Decoder Module is on page 8A-133-1 (in later years it's called the "theft deterrent module" = TDM)

KWR

Thanks! I'll work on this now.

KWR

Checked fuses. Connected power to fuel pump prime and nothing, no sounds at all.
Need to find print 8A-11-4 and 8A-21-5. Opening zip files on a phone is rough.
Where is the Theft Deterrent Module?

Injuneer

If supplying 12 volts to the fuel pump prime connector did not start the fuel pump, you need to check for 12 volts at the gray wire in the harness connector. The prime connector bypasses the fuse and the relay.

http://shbox.com/1/fuel_pump_connector.jpg

http://shbox.com/1/fuel_pump_wiring.jpg

The TDM is called the PASS-Key II Decoder Module in 1993. It is located "in instrument panel, just right of the radio, attached to the air bag bracket."

KWR

Ok, where’s that connection located? I can’t tell, sorry

Injuneer

The fuel pump connector is under the car, on the vertical sheet metal in front of the rear axle assembly, driver side..

GaryDoug

He went away after you told him it was under the car. I do not blame him ;-)

KWR

Trust me, that doesn’t scare me at all. I have too many other projects to juggle.