1450-1451 / 1904
ENGINE
DTC
DESCRIPTION
CAUSE
DIAGNOSTIC
LAMP (
MIL
)
DIAGNOSTIC
LAMP (
CEL
)
Gil When
Driven In CNG
PROBABLE TROUBLE AREA
P1204
CNG Cylinder 2
Injector Open /
Short circuit to
battery
Open Circuit Short
to battery
ON
OFF
OFF
P1204
CNG Cylinder 2
Injector Open /
Short circuit to
battery
Open Circuit Short
to battery
ON
OFF
OFF
P1205
CNG Cylinder 1
Injector short to
ground
Short Circuit to
Ground
ON
OFF
OFF
P1300
Engine Stall due
to Misfire Without
Phase information
OFF
OFF
OFF
1) Loose /Damaged Connections.
2) Faulty IGN System (SPARK PLUGS, HT CABLES,
CONNECTIONS ETC.)
3) Faulty/ Clogged INJECTORS.
4) Low COMPRESSION PRESSURE.
5) Improper VALVE CLEARANCE
6) Improper VALVE TIMING.
7) Faulty ECT Sensor.
8) Loose Connector/ Faulty ECU.
P1301
Ignition Coil
Primary circuit
short to battery/
Current overload
in IGBT with error
in System voltage
Short Circuit to
Battery
ON
OFF
ON
1) Loose /Damaged connector.
2) IGN Coil Control line Short to Battery/ Ground.
3) Check the continuity from Ignition Coil connector pins to the ECU pins (ECU pin 256-Ignition Coil pin 2 & ECU pin 156- Ignition Coil pin
1).12 volts should come at ignition ON.
4) Check for back out of pins at both Ignition Coil connector and ECU connector.
5) Faulty Ignition Coil/ HT Leads/ Spark Plugs.
6)Faulty ECU
P1303
Misfiring Gasoline
Mode
1) When misfire
percentage is more
than a calibrated
OBD emission
Threshold
ON
OFF
Special
Case
1) Loose /Damaged Connections.
2) Faulty IGN System (SPARK PLUGS, HT CABLES, CONNECTIONS ETC.)
3) Faulty/ Clogged INJECTORS.
4) Low COMPRESSION PRESSURE.
5) Improper VALVE CLEARANCE
6) Improper VALVE TIMING.
7) Faulty ECT SENSOR.
8) LOOSE CONNECTOR/ Faulty ECU.
2) When the misfire
percentage is more
than the catalyst
damaging index
ON
OFF
Special
Case
P1304
Misfiring CNG
Mode
1) When misfire
percentage is more
than a calibrated
OBD emission
Threshold
ON
OFF
Special
Case