4
FAULT CODE DEFINITIONS FOR EEC-IV SYSTEMS (63 - 68)
TEST
CODE
CONDITION
63
O, C
63
C, O
64
O, C
65
R
65
R
65
C
66
R, C
66
C
66
O, C
67
O
67
C
67
C
67
O, R
67
O, C
68
O, C
68
O, R, C
68
C
Chapter 4
FAULT CODE DEFINITION
Throttle Position (TP) circuit fault, below
minimum voltage
Fuel injection pump lever sensor input is
less than self test minimum (Diesel)
ACT (IAT)/vane air temperature sensor
fault or circuit grounded
Overdrive Cancel Switch not changing
state (E40D); transmission fault
(Trucks ONLY): Charging system (1985
through 1988 models)
(Cars ONLY): Fuel injector never went
closed loop
(Cars ONLY): VAF/mass air flow sensor
fault, below minimum voltage
(Trucks ONLY): MAF circuit below voltage
(4.0L models)
TOT sensor signal input below self-test
minimum, or vane air flow circuit below
minimum (E4OD)
Neutral Pressure Switch (NPS) circuit
failure, circuit open (3.0L MAP, 3.0L MAF-
SFI, 3.8L SFI)
(Cars ONLY): Clutch switch circuit failure
(Trucks ONLY): Air conditioning
compressor clutch switch fault
(Cars ONLY): Neutral Drive Switch (NDS)
circuit failure, circuit open; or A/C input
high
(Cars ONLY): Manual Lever Position
(MLP) sensor out of range; or A/C input
high (4.9L MAP, 5.8L MAP)
(Cars ONLY): Vane air temperature circuit
grounded
(Cars ONLY): Transmission temperature
switch circuit failure; circuit open
(Trucks ONLY): Transmission oil
temperature over heat
Retrieving Codes
52