DTC P0135 (2.4 L Engine) (2017 2018 2019)

DTC P0135  : A/F Sensor (Sensor 1) Heater Circuit Malfunction

NOTE:  Before you troubleshoot, review the general troubleshooting information .

DTC (PGM-FI)

1. Problem verification

   -1. Turn the vehicle to the ON mode.

   -2. Clear the DTC with the HDS.

   -3. Start the engine. Hold the engine speed at 3, 000 rpm without load (in P or N) until the radiator fan comes on.

   -4. Check for Pending or Confirmed DTCs with the HDS.

   DTC Description	Confirmed DTC	Pending DTC
   P0135 A/F Sensor (Sensor 1) Heater Circuit Malfunction

   Is DTC P0135 indicated?

   YES 

   The failure is duplicated. Go to step 2.

   NO 

   Intermittent failure, the system is OK at this time. Check for poor connections or loose terminals at the A/F sensor (Sensor 1), the relay circuit board (PGM-FI subrelay circuit), and the PCM. If the on-board snapshot of this DTC is recorded, try to reproduce the failure under the same conditions with the on-board snapshot .

2. DTC check

   -1. Check for Pending or Confirmed DTCs with the HDS.

   DTC Description	Confirmed DTC	Pending DTC
   P1658 ETCS Control Relay ON Malfunction
   P1659 ETCS Control Relay OFF Malfunction

   Is DTC P1658 and/or P1659 indicated?

   YES 

   Go to the indicated DTC's troubleshooting.

   NO 

   Go to step 3.

3. Fuse check

   -1. Turn the vehicle to the OFF (LOCK) mode.

   -2. Check the following fuse.

   Fuse	No. A11 (7.5 A)
   Location	Under-hood fuse/relay box

   Is the fuse OK?

   YES 

   Go to step 4.

   NO 

   Repair a short in the IGPS (LAF) wire between the No. A11 (7.5 A) fuse in the under-hood fuse/relay box and the A/F sensor (Sensor 1). Also replace the No. A11 (7.5 A) fuse.

4. A/F sensor (Sensor 1) internal heater resistance check

   -1. Disconnect the following connector.

   A/F sensor (Sensor 1) 4P connector

   -2. At the sensor side, measure the resistance between test points 1 and 2.

   Test condition	Vehicle OFF (LOCK) mode
   	A/F sensor (Sensor 1) 4P connector: disconnected
   Test point 1	A/F sensor (Sensor 1) 4P connector (male terminals) No. 3 (A/F sensor (Sensor 1) side):
   Test point 2	A/F sensor (Sensor 1) 4P connector (male terminals) No. 4 (A/F sensor (Sensor 1) side):

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

   Is there 2.2-2.7 Ω at room temperature?

   YES 

   Go to step 5.

   NO 

   Replace the A/F sensor (Sensor 1) .

5. A/F sensor (Sensor 1) internal circuit check

   -1. At the sensor side, check for continuity under the following conditions.

   Test condition	Vehicle OFF (LOCK) mode
   	A/F sensor (Sensor 1) 4P connector: disconnected

   Test condition	Vehicle OFF (LOCK) mode
   	A/F sensor (Sensor 1) 4P connector: disconnected
   Test point 1	A/F sensor (Sensor 1) 4P connector (male terminals) No. 3 (A/F sensor (Sensor 1) side):
   	A/F sensor (Sensor 1) 4P connector (male terminals) No. 4 (A/F sensor (Sensor 1) side):
   Test point 2	A/F sensor (Sensor 1) 4P connector (male terminals) No. 1 (A/F sensor (Sensor 1) side):

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

   Is there continuity?

   YES 

   Replace the A/F sensor (Sensor 1) .

   NO 

   Go to step 6.

6. Shorted wire check (AFHT line)

   -1. Jump the SCS line with the HDS, and wait more than 1 minute.

   -2. Disconnect the following connector.

   PCM connector C (51P)

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

   Test condition	Vehicle OFF (LOCK) mode
   	A/F sensor (Sensor 1) 4P connector: disconnected
   	PCM connector C (51P): disconnected
   Test point 1	PCM connector C (51P) No. 7
   Test point 2	Body ground

   Is there continuity?

   YES 

   Repair a short in the AFHT wire between the PCM (C7) and the A/F sensor (Sensor 1).

   NO 

   The AFHT wire is not shorted. Go to step 7.

7. Open wire check (AFHT line)

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

   Test condition	Vehicle OFF (LOCK) mode
   	A/F sensor (Sensor 1) 4P connector: disconnected
   	PCM connector C (51P): disconnected
   Test point 1	A/F sensor (Sensor 1) 4P connector (female terminals) No. 3:
   Test point 2	PCM connector C (51P) No. 7

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

   Is there continuity?

   YES 

   The AFHT wire is OK. Go to step 8.

   NO 

   Repair an open in the AFHT wire between the PCM (C7) and the A/F sensor (Sensor 1).

8. Open wire check (IGPS (LAF)/LAF+ line)

   -1. Turn the vehicle to the ON mode.

   -2. Measure the voltage between test points 1 and 2.

   Test condition	Vehicle ON mode
   	A/F sensor (Sensor 1) 4P connector: disconnected
   	PCM connector C (51P): disconnected
   Test point 1	A/F sensor (Sensor 1) 4P connector (female terminals) No. 4:
   Test point 2	Body ground

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

   Is there battery voltage?

   YES 

   The IGPS (LAF)/LAF+ wire is OK. Check for any authorized service information related to the DTCs or symptoms you are troubleshooting or substitute a known-good PCM .

   NO 

   Repair an open in the IGPS (LAF)/LAF+ wire between the A/F sensor (Sensor 1) and the relay circuit board (PGM-FI subrelay circuit).