My 90 5.7 is showing code 54
54. Low voltage at fuel pump OR Low voltage at Fuel pump relay OR Output failure at quad driver module

It needs to crank longer then usual to start.

Looked in the service manual and not finding anything for code 54.

searched for 14103304 relay on line and not finding a new replacement to try

 

RY109 standard motors, have you checked the power off the splice going to the ecm
off the ops ?

 

54Fuel pump
circuit

• Voltage at
  terminal B2 is less than 2 volts for 1.5 seconds since last reference pulse was received.
  
• Faulty fuel pump
  relay, circuit and connections.
  
• Faulty oil pressure switch.

 

OPS ?

 

Ordered relay.

Fuel pump not priming when I turn the key to run

 

Check fuse next to the battery , here’s the schematic and shows E13

 

oil pressure switch

 

Fuse is good
Have power to the relay
Relay clicks when key is turned on then clicks again a few seconds later

Wont be able to get to the OPS until later in the week

 

Have power to the orange wire at the relay

No power at the gray wire

 

Ops is backup for fp relay, follow the code 54 troubleshoot tree

 

Found the code 54 Troubleshoot Tree

The tests indicate a faulty relay

Relay ordered and will install when it arrives

Big thanks to Tuned Performance

 

Relay fixed the problem.

Bought the service manual when I purchased the car new, First time I used it for a repair.