DTC P029B:00 [MZ-CD 1.6]

id0102g8277500

DTC P029B:00

Cylinder No.1 - fuel trim at min limit

DETECTION CONDITION

•  The PCM monitors the cylinder balance. If the cylinder balance decreases below the minimum value of the threshold value, the PCM determines cylinder No.1 - fuel trim at minimum limit.

POSSIBLE CAUSE

•  Fuel injector correction factors improperly

•  Fuel injector No.1 connector or terminal malfunction

•  Fuel injector No.1 malfunction

•  PCM connector or terminal malfunction

•  Fuel injector No.1 + and - circuit short to each other

•  Short to ground in the wiring harness between fuel injector No.1 terminal A and PCM terminal 3AT

•  Short to ground in the wiring harness between fuel injector No.1 terminal B and PCM terminal 3AP

•  Short to power supply in the wiring harness between fuel injector No.1 terminal A and PCM terminal 3AT

•  Short to power supply in the wiring harness between fuel injector No.1 terminal B and PCM terminal 3AP

•  PCM malfunction

DTC P029B:00	Cylinder No.1 - fuel trim at min limit
DETECTION CONDITION	• The PCM monitors the cylinder balance. If the cylinder balance decreases below the minimum value of the threshold value, the PCM determines cylinder No.1 - fuel trim at minimum limit.
POSSIBLE CAUSE	• Fuel injector correction factors improperly • Fuel injector No.1 connector or terminal malfunction • Fuel injector No.1 malfunction • PCM connector or terminal malfunction • Fuel injector No.1 + and - circuit short to each other • Short to ground in the wiring harness between fuel injector No.1 terminal A and PCM terminal 3AT • Short to ground in the wiring harness between fuel injector No.1 terminal B and PCM terminal 3AP • Short to power supply in the wiring harness between fuel injector No.1 terminal A and PCM terminal 3AT • Short to power supply in the wiring harness between fuel injector No.1 terminal B and PCM terminal 3AP • PCM malfunction

Diagnostic procedure

STEP	INSPECTION		ACTION
1	VERIFY FREEZE FRAME DATA HAS BEEN RECORDED • Has the FREEZE FRAME DATA been recorded?	Yes	Go to the next step.
1		No	Record the FREEZE FRAME DATA on the repair order, then go to the next step.
2	VERIFY RELATED REPAIR INFORMATION AVAILABILITY • Verify related service repair information availability. • Is any related repair information available?	Yes	Perform repair or diagnosis according to the available repair information. • If the vehicle is not repaired, go to the next step.
2		No	Go to the next step.
3	PERFORM FUEL INJECTOR CORRECTION FACTORS • Cool down the engine. • Clear the DTC from the PCM memory using the M-MDS. • Perform the FUEL INJECTOR CORRECTION FACTORS (See FUEL INJECTOR CORRECTION FACTORS [MZ-CD 1.6].) • Perform the DIESEL PATRTICULATE FILTER REGENERATION. (See DIESEL PARTICULATE FILTER STATIC REGENERATION [MZ-CD 1.6].) • Run the vehicle under the FREEZE FRAME DATA stored condition. • Is the same DTC present?	Yes	Go to the next step.
3		No	Go to Step 11.
4	INSPECT FUEL INJECTOR NO.1 CONNECTOR CONDITION • Switch the ignition to off. • Disconnect the fuel injector No.1 connector. • Inspect for poor connection (such as damaged/pulled-out pins, corrosion). • Is there any malfunction?	Yes	Repair or replace the connector and/or terminals, then go to Step 10.
4		No	Go to the next step.
5	INSPECT FUEL INJECTOR NO.1 • Inspect the fuel injector No.1. (See FUEL INJECTOR INSPECTION [MZ-CD 1.6].) • Is there any malfunction?	Yes	Replace the fuel injector No.1, then go to Step 10. (See FUEL INJECTOR REMOVAL/INSTALLATION [MZ-CD 1.6].)
5		No	Go to the next step.
6	INSPECT PCM CONNECTOR CONDITION • Disconnect the PCM connector. • Inspect for poor connection (such as damaged/pulled-out pins, corrosion). • Is there any malfunction?	Yes	Repair or replace the connector and/or terminals, then go to Step 10.
6		No	Go to the next step.
7	INSPECT FUEL INJECTOR NO.1 SIGNAL CIRCUIT AND GROUND CIRCUIT FOR SHORT TO EACH OTHER • Fuel injector No.1 and PCM connectors are disconnected. • Inspect for continuity between fuel injector No.1 terminals A and B (wiring harness-side). • Is there continuity?	Yes	Repair or replace the wiring harness for a possible short to each other, then go to Step 10.
7		No	Go to the next step.
8	INSPECT FUEL INJECTOR NO.1 CIRCUIT FOR SHORT TO GROUND • Fuel injector No.1 connector is disconnected. • Inspect for continuity between the following terminals (wiring harness-side) and body ground: ― Fuel injector No.1 terminal A ― Fuel injector No.1 terminal B • Is there continuity?	Yes	Repair or replace the wiring harness for a possible short to ground, then go to Step 10.
8		No	Go to the next step.
9	INSPECT FUEL INJECTOR NO.1 CIRCUIT FOR SHORT TO POWER SUPPLY CIRCUIT • Fuel injector No.1 and PCM connectors are disconnected. • Switch the ignition to ON. • Inspect for continuity between the following terminals (wiring harness-side): ― Fuel injector No.1 terminal A—PCM terminal 3AT ― Fuel injector No.1 terminal B—PCM terminal 3AP • Is there any voltage?	Yes	Intermittent concern exists. Go to the next step.
9		No	Repair or replace the wiring harness for a possible open circuit, then go to the next step.
10	VERIFY THAT DTC P029B:00 TROUBLESHOOTING IS COMPLETED • Make sure to reconnect all disconnected connectors. • Clear the DTC from the PCM memory using the M-MDS. • Run the vehicle under the FREEZE FRAME DATA stored condition. • Is the same DTC present?	Yes	Repeat the inspection from Step 1. • If the malfunction recurs, replace the PCM. (See PCM REMOVAL/INSTALLATION [MZ-CD 1.6].) Go to the next step.
10		No	Go to the next step.
11	VERIFY AFTER REPAIR PROCEDURE • Perform the after repair procedure. (See AFTER REPAIR PROCEDURE [MZ-CD 1.6].) • Are any DTCs present?	Yes	Go to the applicable DTC inspection. (See DTC TABLE [MZ-CD 1.6].)
11		No	DTC troubleshooting completed.