CONTROL SYSTEM — ECM Terminal Voltage Inspection (Incorrect Voltage / Possible Cause)
F2-143spec tableApplies to engine control module (ECM) terminal voltage diagnosis; A/T-related TCM reference at terminal 1K.
NOTE
B+: Battery positive voltage
ECM Terminal — Incorrect Voltage / Possible Cause
1A
Incorrect voltageAlways 0V
Condition
Possible causeOpen circuit in wiring from Battery to ECM terminal 1A
1B
Incorrect voltageAlways 0V
Condition
Possible causeMain relay malfunction (Refer to page F2-157); Open or short circuit in wiring from main relay to ECM terminal 1B; ROOM 15A fuse burned
1C
Incorrect voltageAlways 0V (starter turns)
Condition
Possible causeOpen or short circuit in wiring from ignition switch to ECM terminal 1C
1D
Incorrect voltageAlways 0V
Condition
Possible causeMain relay (FUEL INJ relay) malfunction (Refer to page F2-157); Open circuit in wiring from ignition switch to data link connector terminal +B; Open or short circuit in wiring from data link connector terminal MEN to ECM terminal 1D
1D
Incorrect voltageAlways approx. B+
Condition
Possible causePoor connection at ECM connector; ECM malfunction
1D
Incorrect voltageAlways approx. 5V
Condition
Possible causeECM malfunction
1E
Incorrect voltageAlways below 2.5V
ConditionMIL always ON
Possible causeShort circuit in wiring from instrument cluster to ECM terminal 1E; ECM malfunction
1E
Incorrect voltageAlways below 2.5V
ConditionMIL never ON
Possible causeOpen circuit in wiring from instrument cluster to ECM terminal 1E
1E
Incorrect voltageAlways approx. B+
Condition
Possible causePoor connection at ECM connector; ECM malfunction
1E
Incorrect voltageAlways below 2.5V
ConditionNo display on Self-Diagnosis Checker
Possible causeMain relay (FUEL INJ relay) malfunction (Refer to page F2-157); Open circuit in wiring from ignition switch to data link connector terminal +B
1E
Incorrect voltageAlways below 2.5V
Condition"88" displayed and buzzer sounds continuously
Possible causeOpen or short circuit in wiring from data link connector terminal FEN to ECM terminal 1E
1E
Incorrect voltageAlways approx. B+
Condition
Possible causePoor connection at ECM connector; ECM malfunction
1F
Incorrect voltage—
Condition
Possible cause—
1G
Incorrect voltageAlways 0V
Condition
Possible causeShort circuit in wiring from ignition control module to ECM terminal 1G
1H
Incorrect voltageAlways below 1.0 (Headlights OK)
Condition
Possible causeOpen or short circuit in wiring from headlight relay to ECM terminal 1H
1I
Incorrect voltageAlways below 1.0V
Condition
Possible causeShort circuit in wiring from data link connector terminal TEN to ECM terminal 1I
1I
Incorrect voltageAlways approx. B+
Condition
Possible causeOpen circuit in wiring from data link connector terminal TEN to ECM terminal 1I; Open circuit in wiring from data link connector terminal GND to ground
1J
Incorrect voltageAlways 0V
Condition
Possible causeShort circuit in wiring from rear window defroster switch to ECM terminal 1J
1J
Incorrect voltageAlways B+
Condition
Possible causeOpen circuit in wiring from rear window defroster switch to ECM terminal 1J
1K
Incorrect voltageAlways below 1.0V
Condition
Possible causeOpen or short circuit in wiring from ECM terminal 1K to TCM terminal 1N
1L
Incorrect voltageAlways below 2.5V
ConditionA/C does not operate
Possible causeA/C relay malfunction; Open circuit in wiring from ignition switch to A/C relay; Open circuit in wiring from A/C relay to ECM terminal 1L
1L
Incorrect voltageAlways below 2.5V
ConditionA/C switch OFF but A/C operates
Possible causeShort circuit in wiring from A/C relay to ECM terminal 1L; ECM malfunction
1L
Incorrect voltageAlways B+
Condition
Possible causePoor connection at ECM connector; ECM malfunction