PleasureCraft Engine Group 5.0L, Diagnostic Manual, Page: 288 / 337

5 - 146 Diagnosis 5.0/5.7/6.0/8.1L
MEFI 4 - PCM
DTC 81 - Fuel Injector Driver B Circuit High, Low or Open
Step Action Value Yes No
1
Was the “On-Board Diagnostic” (OBD) system check Go to OBD
performed? — Go to Step 2 System Check
1. Disconnect the appropriate harness connectors of the
four fuel injectors.
2. Turn ON the ignition, with the engine OFF.
2
3. Using a test lamp connected to a known good ground,
probe the ignition voltage circuits of each fuel injector
on the harness connector.
Does the test lamp illuminate on all four circuits? — Go to Step 3 Go to Step 9
1. Connect the fuel injector test lamp J 34730-2C
between the control circuit and the ignition voltage
circuit of the fuel injector harness connector. Repeat for
3
all four fuel injectors.
2. Start the engine.
Does the test lamp blink on all four fuel injector harness
connectors? — Go to Step 7 Go to Step 4
4
Does the test lamp remain illuminated at all times on any
of the four fuel injector harness connectors? — Go to Step 6 Go to Step 5
Locate and repair an open or short to voltage in the fuel
5
injector control circuit.
Was a problem found? — Verify Repair Go to Step 8
Locate and repair a short to ground in the fuel injector
6
control circuit.
Was a problem found? — Verify Repair Go to Step 11
Locate and repair poor connections at the harness
7
connector of the fuel injector.
Was a problem found? — Verify Repair Go to Step 10
Locate and repair poor connections at the harness
8
connector of the ECM.
Was a problem found? — Verify Repair Go to Step 11
Important: The ECM fuse also supplies voltage to the
ignition coils. If the fuse is open, inspect all related circuits
9
for a short to ground.
Repair an open or short to ground in the fuel injector
ignition voltage circuit.
Was a problem found? — Verify Repair —
10
Replace the fuel injector.
Is action complete? — Verify Repair —
11
Replace the ECM.
Is action complete? — Verify Repair —