Fig. 41: PCM Power And Ground Circuit Troubleshooting Flow Chart (3 Of 3)
Courtesy of AMERICAN HONDA MOTOR CO., INC.
PCM POWER AND GROUND CIRCUIT TROUBLESHOOTING
1. Engine starting check:
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1. Try to start the engine.
Does the engine start and idle smoothly?
YES : GO TO THE F-CAN CIRCUIT TROUBLESHOOTING .
NO : Go to step 2.
2. Determine possible failure area (+B IG MAIN wire shorted, others):
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1. Turn the ignition switch to LOCK (0).
2. Check the following fuse.
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Fuse No. A2-1 (50 A)
Location Under-hood fuse/relay box
Is the fuse OK?
YES : Repair an open in the +B IG MAIN wire between the No. A2-1 (50 A) fuse and the ignition
switch. If the wire is OK, go to step 3.
NO : Repair a short in the +B IG MAIN wire between the No. A2-1 (50 A) fuse and the under-
hood fuse/relay box. Also replace the No. A2-1 (50 A) fuse.
3. Fuse check:
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1. Check the following fuse.
Fuse No. A23 (15 A)
Location Under-hood fuse/relay box
Is the fuse OK?
YES : Go to step 8.
NO : Go to step 4.
4. Determine possible failure area (+B IGP line, others):
ο‘
1. Remove the blown No. A23 (15 A) fuse from the under-hood fuse/relay box.
2. Remove PGM-FI main relay 1 (A) from the under-dash fuse/relay box.
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Fig. 42: Identifying PGM-FI Main Relay 1
Courtesy of AMERICAN HONDA MOTOR CO., INC.
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3. Check for continuity between test points 1 and 2.
Test condition IG LOCK (0)
PGM-FI main relay 1: disconnected
Test circuit +B IGP
Test point 1 PGM-FI main relay 1 4P socket No. 1 (Under-dash fuse/relay box)
Test point 2 Body ground
Test circuit +B IGP
Test point 1 PGM-FI main relay 1 4P socket No. 4 (Under-dash fuse/relay box)
Test point 2 Body ground
Fig. 43: Checking For Continuity Between Test Points 1 And 2
Courtesy of AMERICAN HONDA MOTOR CO., INC.
Is there continuity?
YES : Go to step 5.
NO : Go to step 6.
5. Shorted wire check (+B IGP line):
ο‘
1. Disconnect the following connector.
Under-dash fuse/relay box connector D (32P)
2. Check for continuity between test points 1 and 2.
Test condition IG LOCK (0)
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PGM-FI main relay 1: disconnected
Under-dash fuse/relay box connector D (32P): disconnected
Test circuit +B IGP
Test point 1 Under-dash fuse/relay box connector D (32P) No. 9 (BLU)
Test point 2 Body ground
Fig. 44: Checking For Continuity Between Test Points 1 And 2
Courtesy of AMERICAN HONDA MOTOR CO., INC.
Is there continuity?
YES : Repair a short in the +B IGP wire between the No. A23 (15 A) fuse and the under-dash
fuse/relay box. Also replace the No. A23 (15 A) fuse.
NO : The +B IGP wire is OK. Replace the under-hood fuse/relay box. Also replace the No. A23
(15 A) fuse.
6. Part(s) internal circuit check (short in FI MAIN RLY OUT line):
ο‘
1. Disconnect each of the parts or connectors below, one at a time, then check for continuity
between test points 1 and 2.
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PGM-FI main relay 2
PCM connector A (49P)
Each injector 2P connector
CMP sensor B 3P connector
CKP sensor 3P connector
Electronic throttle control system (ETCS) control relay
Test condition IG LOCK (0)
Test circuit FI MAIN RLY OUT
Test point 1 PGM-FI main relay 1 4P socket No. 2 (Under-hood fuse/relay box)
Test point 2 Body ground
Fig. 45: Checking For Continuity Between Test Points 1 And 2
Courtesy of AMERICAN HONDA MOTOR CO., INC.
Does continuity go away when one of the above components is disconnected?
YES : Replace the part that made the short to body ground go away when it was disconnected. If the part
is the PCM, replace it or substitute a known-good PCM See PCM REMOVAL AND
INSTALLATION or PCM UPDATE, 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 See PCM REMOVAL AND INSTALLATION or PCM
UPDATE. Also replace the No. A23 (15 A) fuse.
NO : Parts are OK. Go to step 7.
7. Shorted wire check (FI MAIN RLY OUT line):
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1. Jump the SCS line with the HDS.
2. Disconnect the following parts:
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PGM-FI main relay 2
PCM connector A (49P)
Injectors
CMP sensor B
CKP sensor
Electronic throttle control system (ETCS) control relay
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3. Check for continuity between test points 1 and 2.
Test condition IG LOCK (0)
PGM-FI main relay 1: disconnected
PGM-FI main relay 2: disconnected
PCM connector A (49P): disconnected
Each injector 2P connector: disconnected
CMP sensor B 3P connector: disconnected
CKP sensor 3P connector: disconnected
Electronic throttle control system (ETCS) control relay: disconnected
Test circuit FI MAIN RLY OUT
Test point 1 PGM-FI main relay 1 4P socket No. 2 (Under-dash fuse/relay box)
Test point 2 Body ground
Fig. 46: Checking For Continuity Between Test Points 1 And 2
Courtesy of AMERICAN HONDA MOTOR CO., INC.
Does continuity go away when one of the above components is disconnected?
YES : Repair a short in the FI MAIN RLY OUT wire between PGM-FI main relay 1 and each part.
Also replace the No. A23 (15 A) fuse.
NO : The FI MAIN RLY OUT wire is OK. Replace PGM-FI main relay 1. Also replace the No.
A23 (15 A) fuse.
8. Fuse check 2:
ο‘
1. Check the following fuse.
Fuse No. B4 (15 A)
Location Under-dash fuse/relay box
Is the fuse OK?
YES : Go to step 13.
NO : Go to step 9.
9. Relay check:
ο‘
1. Remove the blown No. B4 (15 A) fuse from the under-hood fuse/relay box.
2. Remove PGM-FI main relay 2 (A) from the under-dash fuse/relay box.
ο‘
Fig. 47: Identifying PGM-FI Main Relay 2
Courtesy of AMERICAN HONDA MOTOR CO., INC.
ο‘
3. TEST PGM-FI MAIN RELAY 2 .
Is the relay OK?
YES : PGM-FI main relay 2 is OK. Go to step 10.
NO : Replace PGM-FI main relay 2. Also replace the No. B4 (15 A) fuse.
10. Determine possible failure area (IG1 FUEL PUMP line, others):
ο‘
1. Check for continuity between test points 1 and 2.
Test condition IG LOCK (0)
PGM-FI main relay 2: disconnected
Test circuit IG1 FUEL PUMP
Test point 1 PGM-FI main relay 2 4P socket No. 2 (Under-dash fuse/relay box)
Test point 2 Body ground
Fig. 48: Checking For Continuity Between Test Points 1 And 2
Courtesy of AMERICAN HONDA MOTOR CO., INC.
Is there continuity?
YES : Go to step 11.
NO : Go to step 12.
11. Shorted wire check (IG1(F/P) line):
ο‘
1. Jump the SCS line with the HDS.
2. Disconnect the following connector.
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PCM connector C (49P)
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3. Check for continuity between test points 1 and 2.
Test condition IG LOCK (0)
PGM-FI main relay 2: disconnected
PCM connector C (49P): disconnected
Test circuit IG1(F/P)
Test point 1 PCM connector C (49P) No. 10 (WHT)
Test point 2 Body ground
Fig. 49: Checking For Continuity Between Test Points 1 And 2
Courtesy of AMERICAN HONDA MOTOR CO., INC.
Is there continuity?
YES : Repair a short in the IG1(F/P) wire between the No. B4 (15 A) fuse and the PCM (C10),
between the No. B4 (15 A) fuse and PGM-FI main relay 2, or between the No. B4 (15 A) fuse and
the immobilizer control unit. Also replace the No. B4 (15 A) fuse.
NO : The IG1(F/P) wire is OK. Replace the No. B4 (15 A) fuse, and update the PCM See PCM
REMOVAL AND INSTALLATION or PCM UPDATE if it does not have the latest software, or
substitute a known-good PCM See PCM REMOVAL AND INSTALLATION or PCM
UPDATE, 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 See PCM REMOVAL AND INSTALLATION or PCM UPDATE.
12. Shorted wire check (FUEL PUMP RLY OUT line):
ο‘
1. Remove the access panel from the floor.
2. Disconnect the following connector.
ο‘
Fuel tank unit 4P connector
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3. Check for continuity between test points 1 and 2.
Test condition IG LOCK (0)
PGM-FI main relay 2: disconnected
Fuel tank unit 4P connector: disconnected
Test circuit FUEL PUMP RLY OUT
Test point 1 Fuel tank unit 4P connector No. 1 (GRN)
Test point 2 Body ground
Fig. 50: Checking For Continuity Between Test Points 1 And 2
Courtesy of AMERICAN HONDA MOTOR CO., INC.
Is there continuity?
YES : Repair a short in the FUEL PUMP RLY OUT wire between the fuel tank unit 4P connector
and PGM-FI main relay 2. Also replace the No. B4 (15 A) fuse.
NO : The FUEL PUMP RLY OUT wire is OK. Check the fuel pump, and replace it if needed. Also
replace the No. B4 (15 A) fuse.
13. Open wire check (IG1(F/P) line):
ο‘
1. Jump the SCS line with the HDS.
ο‘
2. Disconnect the following connectors.
PCM connector A (49P)
PCM connector C (49P)
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3. Turn the ignition switch to ON (II).
4. Measure the voltage between test points 1 and 2.
Test condition IG ON (II)
PCM connector A (49P): disconnected
PCM connector C (49P): disconnected
Test circuit IG1(F/P)
Test point 1 PCM connector C (49P) No. 10 (WHT)
Test point 2 Body ground
Fig. 51: Measuring Voltage Between Test Points 1 And 2
Courtesy of AMERICAN HONDA MOTOR CO., INC.
Is there battery voltage?
YES : The IG1(F/P) wire is OK. Go to step 14.
NO : Repair an open in the IG1(F/P) wire between the No. B4 (15 A) fuse and the PCM (C10).
14. Determine possible failure area (PGM-FI main relay 1 control circuit, others):
ο‘
1. Measure the voltage between test points 1 and 2.
Test condition IG ON (II)
PCM connector A (49P): disconnected
PCM connector C (49P): disconnected
Test circuit FI MAIN RLY CL-
Test point 1 PCM connectors A (49P) No. 7 (GRY)
Test point 2 Body ground
Fig. 52: Measuring Voltage Between Test Points 1 And 2
Courtesy of AMERICAN HONDA MOTOR CO., INC.
Is there battery voltage?
YES : Go to step 18.
NO : Go to step 15.
15. Determine possible failure area (+B IGP line, others):
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1. Turn the ignition switch to LOCK (0).
ο‘
2. Remove PGM-FI main relay 1 (A) from the under-dash fuse/relay box.
Fig. 53: Identifying PGM-FI Main Relay 1
Courtesy of AMERICAN HONDA MOTOR CO., INC.
ο‘
3. Measure the voltage between test points 1 and 2.
Test condition IG LOCK (0)
PCM connector A (49P): disconnected
PCM connector C (49P): disconnected
PGM-FI main relay 1: disconnected
Test circuit +B IGP
Test point 1 PGM-FI main relay 1 4P socket No. 4 (Under-dash fuse/relay box)
Test point 2 Body ground
Fig. 54: Measuring Voltage Between Test Points 1 And 2
Courtesy of AMERICAN HONDA MOTOR CO., INC.
Is there battery voltage?
YES : Go to step 17.
NO : Go to step 16.
16. Open wire check (+B IGP line):
ο‘
1. Disconnect the following connector.
Under-dash fuse/relay box connector D (32P)
2. Measure the voltage between test points 1 and 2.
Test condition IG LOCK (0)
ο‘
PCM connector A (49P): disconnected
PCM connector C (49P): disconnected
PGM-FI main relay 1: disconnected
Under-dash fuse/relay box connector D (32P): disconnected
Test circuit +B IGP
Test point 1 Under-dash fuse/relay box connector D (32P) No. 9 (BLU)
Test point 2 Body ground
Fig. 55: Measuring Voltage Between Test Points 1 And 2
Courtesy of AMERICAN HONDA MOTOR CO., INC.
Is there battery voltage?
YES : The +B IGP wire is OK. Replace the under-hood fuse/relay box.
NO : Repair an open in the +B IGP wire between the No. A23 (15A) fuse and the under-dash
fuse/relay box.
17. Open wire check (FI MAIN RLY CL- line):
ο‘
1. Check for continuity between test points 1 and 2.
Test condition IG LOCK (0)
PCM connector A (49P): disconnected
PCM connector C (49P): disconnected
PGM-FI main relay 1: disconnected
Test circuit FI MAIN RLY CLT-
Test point 1 PCM connector A (49P) No. 7 (GRY)
Test point 2 PGM-FI main relay 1 4P socket No. 3 (Under-dash fuse/relay box)
Fig. 56: Checking For Continuity Between Test Points 1 And 2
Courtesy of AMERICAN HONDA MOTOR CO., INC.
Is there continuity?
YES : The FI MAIN RLY CL- wire is OK. TEST PGM-FI MAIN RELAY 1 . If the relay is OK,
update the PCM See PCM REMOVAL AND INSTALLATION or PCM UPDATE if it does
not have the latest software, or substitute a known-good PCM See PCM REMOVAL AND
INSTALLATION or PCM UPDATE, 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 See PCM REMOVAL AND INSTALLATION or
PCM UPDATE.
NO : Repair an open in the FI MAIN RLY CL- wire between the PCM (A7) and PGM-FI main
relay 1.
18. Determine possible failure area (+B IGP line, others):
ο‘
1. Turn the ignition switch to LOCK (0).
ο‘
2. Remove PGM-FI main relay 1 (A) from the under-dash fuse/relay box.
Fig. 57: Identifying PGM-FI Main Relay 1
Courtesy of AMERICAN HONDA MOTOR CO., INC.
ο‘
3. Measure the voltage between test points 1 and 2.
Test condition IG LOCK (0)
PCM connector A (49P): disconnected
PCM connector C (49P): disconnected
PGM-FI main relay 1: disconnected
Test circuit +B IGP
Test point 1 PGM-FI main relay 1 4P socket No. 1 (Under-dash fuse/relay box)
Test point 2 Body ground
Fig. 58: Measuring Voltage Between Test Points 1 And 2
Courtesy of AMERICAN HONDA MOTOR CO., INC.
Is there battery voltage?
YES : Go to step 20.
NO : Go to step 19.
19. Open wire check (+B IGP line):
ο‘
1. Disconnect the following connector.
Under-dash fuse/relay box connector D (32P)
2. Measure the voltage between test points 1 and 2.
Test condition IG LOCK (0)
ο‘
PCM connector A (49P): disconnected
PCM connector C (49P): disconnected
PGM-FI main relay 1: disconnected
Under-dash fuse/relay box connector D: disconnected
Test circuit +B IGP
Test point 1 Under-dash fuse/relay box connector D (32P) No. 9 (BLU)
Test point 2 Body ground
Fig. 59: Measuring Voltage Between Test Points 1 And 2
Courtesy of AMERICAN HONDA MOTOR CO., INC.
Is there battery voltage?
YES : The +B IGP wire is OK. Replace the under-hood fuse/relay box.
NO : Repair an open in the +B IGP wire between the No. A23 (15 A) fuse and the under-dash
fuse/relay box.
20. Open wire check (FI MAIN RLY OUT line):
ο‘
1. Check for continuity between test points 1 and 2.
Test condition IG LOCK (0)
PCM connector A (49P): disconnected
PCM connector C (49P): disconnected
PGM-FI main relay 1: disconnected
Test circuit FI MAIN RLY OUT
Test point 1 PCM connector A (49P) No. 9 (BRN)
Test point 2 PGM-FI main relay 1 4P socket terminal No. 2 (Under-dash fuse/relay box)
Fig. 60: Checking For Continuity Between Test Points 1 And 2
Courtesy of AMERICAN HONDA MOTOR CO., INC.
Is there continuity?
YES : The FI MAIN RLY OUT wire is OK. Go to step 21.
NO : Repair an open in the FI MAIN RLY OUT wire between the PCM (A9) and PGM-FI main
relay 1.
21. Relay check:
1. TEST PGM-FI MAIN RELAY 1 .
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Is PGM-FI main relay 1 OK?
YES : PGM-FI main relay 1 is OK. Go to step 22.
NO : Replace PGM-FI main relay 1.
22. Open wire check (PG1, LG2 lines):
ο‘
1. Disconnect the following connector.
PCM connectors B (49P)
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2. Check for continuity between these test points and body ground individually.
Test condition IG LOCK (0)
PCM connector A (49P): disconnected
PCM connector B (49P): disconnected
PCM connector C (49P): disconnected
PGM-FI main relay 1: disconnected
Connector
Test circuit Terminal
PCM connector B (49P)
PG2
PG1
PG1
PG1
LG2
No. 1 (BLK)
No. 10 (BLK)
No. 2 (BLK)
No. 15 (BRN)
No. 20 (BRN)
PCM connector C (49P)
Fig. 61: Checking For Continuity Between PCM Connector B (49P) Terminals And Body
Ground
Courtesy of AMERICAN HONDA MOTOR CO., INC.
Fig. 62: Checking For Continuity Between PCM Connector C (49P) Terminals And Body
Ground
Courtesy of AMERICAN HONDA MOTOR CO., INC.
Is there continuity?
YES : The PG1/PG2/LG2 wires are OK. Update the PCM See PCM REMOVAL AND
INSTALLATION or PCM UPDATE if it does not have the latest software, or substitute a
known-good PCM See PCM REMOVAL AND INSTALLATION or PCM UPDATE, 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 See PCM REMOVAL AND INSTALLATION or PCM UPDATE.
NO : Repair an open in the PG1, PG2, and/or LG2 wire between the PCM (B1, B10, C2, C15, C20)
and G101.
PCM UPDATE
Special Tool Required
Image
Description/Tool Number
2024 Honda CR-V Owner's Manual
2023 Honda CR-V Owner's Manual
2021 Honda CR-V Owner's Manual
2018 Honda CR-V Owner's Manual
2015 Honda CR-V Owner's Manual
