'06-08 models

NOTE: Before beginning this troubleshooting procedure, refer to the SYMPTOM TROUBLESHOOTING INDEX .

Check for the PGM-FI DTCs (see GENERAL TROUBLESHOOTING INFORMATION ).
Check the No. 11 (20 A) fuse in the under-hood fuse/relay box, and the No. 30 (7.5 A) fuse in the under-dash fuse/relay box.
Are the fuses OK?

YES - Go to step 3.

NO - Replace the fuse(s) and recheck.
Remove the radiator fan relay from the under-hood fuse/relay box, and test it (see POWER RELAY TEST ).
Is the relay OK?

YES - Go to step 4.

NO - Replace the radiator fan relay.
Measure the voltage between radiator fan relay 4P socket terminal No. 2 and body ground.

Fig 1: Measuring Voltage Between Radiator Fan Relay 4P Socket Terminal No. 2 And Body Ground
Courtesy of AMERICAN HONDA MOTOR CO., INC.

Is there battery voltage?

YES - Go to step 5.

NO - Replace the under-hood fuse/relay box.
Connect radiator fan relay 4P socket terminal No. 1 and No. 2 with a jumper wire.

Fig 2: Connecting Radiator Fan Relay 4P Socket Terminal No. 1 And No. 2 With A Jumper Wire
Courtesy of AMERICAN HONDA MOTOR CO., INC.

Does the radiator fan run?

YES - Go to step 6.

NO - Go to step 7.
Disconnect the jumper, and turn the ignition switch ON (II). Check for voltage between radiator fan relay 4P socket terminal No. 3 and body ground.

Fig 3: Checking Voltage Between Radiator Fan Relay 4P Socket Terminal No. 3 And Body Ground
Courtesy of AMERICAN HONDA MOTOR CO., INC.

Is there battery voltage?

YES - Go to step 10.

NO - Repair open in the wire between the under-hood fuse/relay box and under-dash fuse/relay box.
Disconnect the radiator fan motor 2P connector.
Check for continuity between radiator fan relay 4P socket terminal No. 1 and radiator fan motor 2P connector terminal No. 2.

Fig 4: Checking Continuity Between Radiator Fan Relay 4P Socket Terminal No. 1 And Radiator Fan Motor 2P Terminal No. 2
Courtesy of AMERICAN HONDA MOTOR CO., INC.

Is there continuity?

YES - Go to step 9.

NO - Repair open in the wire between the under-hood fuse/relay box and radiator fan motor 2P connector terminal No. 2.a
Check for continuity between radiator fan motor 2P connector terminal No. 1 and body ground.

Fig 5: Checking Continuity Between Radiator Fan Motor 2P Connector Terminal No. 1 And Body Ground
Courtesy of AMERICAN HONDA MOTOR CO., INC.

Is there continuity?

YES - Replace the radiator fan motor (see RADIATOR AND FAN REPLACEMENT ).

NO - Repair open in the wire between radiator fan motor 2P connector terminal No. 1 and body ground. If the wire is OK, check for a poor ground at G301.
Connect the Honda Diagnostic System (HDS) to the data link connector (DLC) (see step 2 on HOW TO USE THE HDS (HONDA DIAGNOSTIC SYSTEM) ).
Turn the ignition switch ON (II).
'07-08 models: Make sure the HDS communicates with the vehicle and the engine control module (ECM)/power train control module (PCM). If it doesn't communicate, troubleshoot the DLC circuit (see '07-08 MODELS ).
Jump the SCS line with the HDS, then turn the ignition switch OFF.
NOTE: This step must be done to protect the ECM/PCM from damage.
Disconnect ECM/PCM connector E (31P).
Disconnect under-hood fuse/relay box connector E (16P).
Check for continuity between ECM/PCM connector terminal E12 and under-hood fuse/relay box terminal E14.

Fig 6: Checking Continuity Between ECM/PCM Connector Terminal E12 And Under-Hood Fuse/Relay Box Terminal E14
Courtesy of AMERICAN HONDA MOTOR CO., INC.

Is there continuity?

YES - Circuit is OK. Update the ECM/PCM if it does not have the latest software (see UPDATING THE ECM/PCM ), or substitute a known-good ECM/PCM (see SUBSTITUTING THE ECM/PCM ), then recheck. if the symptom/indication goes away with a known-good ECM/PCM, replace the original ECM/PCM (see ECM/PCM REPLACEMENT ).

NO - Repair open in the wire between the under-hood fuse/relay box and the ECM/PCM.