STEP/SEQUENCE
RESULT
WHAT TO DO NEXT
TM 9-2320-363-20-1
Section 4
TROUBLESHOOTING CHARTS
E. FLASH CODE: 54
J1587 CODE:
P84 12 - VEHICLE SPEED SENSOR FAULT
54-3
Check for Short to
Ground
Turn ignition off.
Less than or
Either the signal wire (ckt #556)
Disconnect the ECM vehicle
equal to 10,000 ohms
or the return wire (ckt #557) is
harness connector.
on either reading.
shorted to ground. Repair short.
Read resistance between socket
Then go to 54-30.
E2 (ckt #556) and a good ground.
Also read resistance between
Greater than
Go to 54-4.
socket E3 (ckt #557) and a good
10,000 ohms on
ground.
both readings.
54-4
Check Vehicle Speed
Sensor
Read resistance of Vehicle
Less than
Go to 54-5.
Speed Sensor across the vehicle
50 ohms.
sped sensor connector pins.
From 50 to
Go to 54-6.
3,000 ohms.
Greater than
Go to 54-5.
3,000 ohms or open.
54-5
Check VSS Connectors
Inspect terminals at VSS
Terminals and
Replace VSS. Then go to 54-30.
connectors (sensor side and
connectors are okay.
harness side) for damage,
corrosion, and unseated pins or
Problem found.
Repair terminals/connectors.
sockets.
Then go to 54-30
54-6
Check for Short to
Power
Turn ignition on.
Less than or
Go to 54-7.
Read voltage at the ECM vehicle
equal to 4 volts.
harness connector, socket E3
(ckt #557) to a good ground
Greater than
The VSS or VSS return line
4 volts.
(ckt #557) is shorted to battery or
some other source of voltage.
Repair short. Then to 54-30.
Change 3 3-345.355
