Injector Control Module Circuit Troubleshooting (R18A9)

1. Shorted wire check (INJ/CNG_INJ line):

- 1. Turn the ignition switch to LOCK (0).

- 2. Disconnect the following connectors.

Injector control module 26P connector

No. 1 - No. 4 injector 2P connectors

- 3. Check for continuity between test points 1 and 2.

Test condition	IG LOCK (0)
	Injector control module 26P connector: disconnected
	Injector 2P connectors: disconnected
Test circuit	INJ
Test point 1	Injector 2P connector No. 1 (see table)
Test point 2	Body ground

INJECTOR	WIRE COLOR
No. 1	BRN
No. 2	RED
No. 3	BLU
No. 4	YEL

Courtesy of HONDA, U.S.A., INC.

Is there continuity?

YES

Repair a short in the INJ/CNG_INJ line wire between the injector control module and the injector.

The INJ/CNG_INJ wire is not shorted. Go to step 2.

2. Open wire check (INJ/CNG_INJ line):

- 1. Connect terminals A and B with a jumper wire.

Terminal A	Injector 2P connector No. 1 (see table)
Terminal B	Body ground

INJECTOR	WIRE COLOR
No. 1	BRN
No. 2	RED
No. 3	BLU
No. 4	YEL

Courtesy of HONDA, U.S.A., INC.

- 2. Check for continuity between test points 1 and 2.

Test condition	IG LOCK (0)
	Injector control module 26P connector: disconnected
	Injector 2P connectors: disconnected
	Injector 2P connector terminal No. 1: jumped to body ground
Test circuit	CNG_INJ
Test point 1	Injector control module 26P connector (see table)
Test point 2	Body ground

INJECTOR CONTROL MODULE TERMINAL	TERMINAL NAME	WIRE COLOR
No. 12	CNG_INJ1	RED
No. 13	CNG_INJ2	BLU
No. 25	CNG_INJ3	GRN
No. 26	CNG_INJ4	BRN

Courtesy of HONDA, U.S.A., INC.

Is there continuity?

YES

The INJ/CNG_INJ wire is OK. Go to step 3.

Repair an open in the INJ/CNG_INJ wire between the injector control module and the injector.

3. Shorted wire check (INJ_CNTL line, INJ_MODE line):

- 1. Jump the SCS line with the HDS.

- 2. Disconnect the following connectors.

PCM connector A (49P)

PCM connector C (49P)

- 3. Check for continuity between test points 1 and 2.

Test condition	IG LOCK (0)
	Injector control module 26P connector: disconnected
	All Injector 2P connectors: disconnected
	PCM connector A: disconnected
	PCM connector C: disconnected
Test circuit	INJ_CNTL, INJ_MODE
Test point 1	PCM connector A and C (see table)
Test point 2	Body ground

PCM	PCM TERMINAL NAME	WIRE COLOR
C5	INJ_CNTL1	BRN/BLK
C6	INJ_CNTL2	RED/BLK
C7	INJ_CNTL3	BLU/BLK
C8	INJ_CNTL4	YEL/BLK
A6	INJ_MODE	ORN

Courtesy of HONDA, U.S.A., INC.

Courtesy of HONDA, U.S.A., INC.

Is there continuity?

YES

Repair a short in the INJ_CNTL or INJ_MODE wire between the injector control module and PCM.

The INJ_CNTL and INJ_MODE wires are not shorted. Go to step 4.

4. Open wire check (INJ_CTRL line, INJ_MODE line):

- 1. Connect terminals A and B with a jumper wire.

Terminal A	Injector control module 26P connector (see table)
Terminal B	Body ground

INJECTOR CONTROL MODULE TERMINAL	TERMINAL NAME	WIRE COLOR
No. 3	INJ1_CTRL1	YEL
No. 4	INJ1_CTRL2	GRY
No. 5	INJ1_CTRL3	PNK
No. 6	INJ1_CTRL4	LT GRN
No. 16	INJ_MODE	ORN

Courtesy of HONDA, U.S.A., INC.

- 2. Check for continuity between test points 1 and 2.

Test condition	IG LOCK (0)
	Injector control module 26P connector: disconnected
	All Injector 2P connectors: disconnected
	PCM connector A: disconnected
	PCM connector C: disconnected
	Injector control module 26P connector: jumped to body ground
Test circuit	INJ_CNTL, INJ_MODE
Test point 1	PCM connector A and C (see table)
Test point 2	Body ground

PCM	PCM TERMINAL NAME	WIRE COLOR
C5	INJ_CNTL1	BRN/BLK
C6	INJ_CNTL2	RED/BLK
C7	INJ_CNTL3	BLU/BLK
C8	INJ_CNTL4	YEL/BLK
A6	INJ_MODE	ORN

Courtesy of HONDA, U.S.A., INC.

Courtesy of HONDA, U.S.A., INC.

Is there continuity?

YES

The INJ_CTRL and INJ_MODE wires are OK. Go to step 5.

Repair an open in the INJ_CTRL wire or INJ_MODE wire between the injector control module and the PCM.

5. Open wire check (INJIGP/IGP line):

- 1. Remove the jumper wire.

- 2. Reconnect the following connectors.

PCM connector A (49P)

PCM connector C (49P)

- 3. Turn the ignition switch to ON (II), then measure the voltage between test points 1 and 2.

Test condition	IG ON (II)
	Injector control module 26P connector: disconnected
	All Injector 2P connectors: disconnected
Test circuit	INJIGP
Test point 1	Injector control module 26P connector No. 1 (YEL), No. 14 (YEL)
Test point 2	Body ground

Test circuit	IGP
Test point 1	Injector 2P connector No. 2 (YEL/GRN)
Test point 2	Body ground

Courtesy of HONDA, U.S.A., INC.

Courtesy of HONDA, U.S.A., INC.

Is there battery voltage?

YES

The INJIGP/IGP wires are OK. Go to step 6.

Check the injector control module relay circuit .

6. Open wire check (PG_INJ_DRIVER lines, LG lines):

- 1. Turn the ignition switch to LOCK (0).

- 2. Check for continuity between test points 1 and 2.

Test condition	IG LOCK (0)
	Injector control module 26P connector: disconnected
	All Injector 2P connectors: disconnected
Test circuit	PG_INJ_DRIVER, LG
Test point 1	Injector control module 26P connector (see table)
Test point 2	Body ground

INJECTOR CONTROL MODULE TERMINAL	TERMINAL NAME	WIRE COLOR
No. 2	LG	BRN
No. 11	PG_INJ_DRIVER	GRY
No. 15	LG	BRN
No. 24	PG_INJ_DRIVER	GRY

Courtesy of HONDA, U.S.A., INC.

Is there continuity?

YES

The PG_INJ_DRIVER and LG wires are OK. Go to step 7.

Repair open in the PG_INJ_DRIVER and/or LG wire(s) between the injector control module and G101.

7. Injector control module check (substitution):
- 1. Substitute a known-good injector control module.

- 2. Reconnect all connectors.

- 3. Try to start the engine.

Does the engine start?

YES

Replace the original injector control module.

NO

The injector control module is OK. Go to step 8
8. Injector operation check:
- 1. Turn the ignition switch to LOCK (0).

- 2. Turn the ignition switch to ON (II), and listen for a clicking sound from the injectors within 2 seconds.

Do all the injectors click?

YES

The injector is OK. Update the PCM - Refer to: ECM/PCM Update , ECM Removal and Installation (K24Z7) , ECM/PCM Removal and Installation (Except K24Z7 and R18Z1 (CVT)) if it does not have the latest software, or substitute a known-good PCM - Refer to: ECM/PCM Update , ECM Removal and Installation (K24Z7) , ECM/PCM Removal and Installation (Except K24Z7 and R18Z1 (CVT)) , then recheck. If the symptom/indication goes away and the PCM was updated, troubleshooting is complete. If the symptom/indication goes away and the PCM was substituted, replace the original PCM - Refer to: ECM/PCM Update , ECM Removal and Installation (K24Z7) , ECM/PCM Removal and Installation (Except K24Z7 and R18Z1 (CVT)) .

NO

Go to step 9.

9. Injector internal resistance check:

- 1. Turn the ignition switch to LOCK (0).

- 2. Disconnect the following connector.

Injector 2P connector (problem cylinder)

- 3. Measure the resistance between test point 1 and 2.

Test condition	IG LOCK (0)
	Injector 2P connectors: disconnected
Test circuit	INJIGP, INJ
Test point 1	Injector 2P connector No. 1 (injector side)
Test point 2	Injector 2P connector No. 2 (injector side)

Courtesy of HONDA, U.S.A., INC.

Is there 1.14 - 1.26 - at room temperature-

YES

Check for poor connections or loose terminals at injector control module, the injector, and the PCM.

Replace the injector(s). - Refer to: Injector Removal and Installation (K24Z7) , Injector Removal and Installation (R18A9) , Injector Removal and Installation (R18Z1 (A/T, M/T)) , Injector Removal and Installation (R18Z1 (CVT)) ('14 - '15)