DTC P0140

DTC P0140  : Secondary HO2S (Sensor 2) Circuit No Activity

NOTE: 

• Before you troubleshoot, review the general troubleshooting information .
• Check for damage or corrosion at secondary HO2S (Sensor 2) connector terminals.

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.

   -4. Hold the engine speed at 3, 000 rpm without load (in neutral) until the radiator fan comes on, then let it idle.

   -5. Check for Pending or Confirmed DTCs with the HDS.

   DTC Description	Confirmed DTC	Pending DTC
   P0140 Secondary HO2S (Sensor 2) Circuit No Activity

   Is DTC P0140 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 secondary HO2S (Sensor 2) 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. Shorted wire check (SO2 line)

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

   -2. Jump the SCS line with the HDS, and wait more than 1 minute.

   -3. Disconnect the following connectors.

   Secondary HO2S (Sensor 2) 4P connector

   PCM connector No. 1 (96P)

   -4. Check for continuity between test points 1 and 2.

   Test condition	Vehicle OFF (LOCK) mode
   	Secondary HO2S (Sensor 2) 4P connector: disconnected
   	PCM connector No. 1 (96P): disconnected
   Test point 1	Secondary HO2S (Sensor 2) 4P connector (female terminals) No. 2:
   Test point 2	Body ground

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

   Is there continuity?

   YES 

   Repair a short in the SO2 wire between PCM connector No. 1 terminal No. 22 and secondary HO2S (Sensor 2).

   NO 

   The SO2 wire is not shorted. Go to step 3.

3. Open wire check (SO2 line)

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

   Test condition	Vehicle OFF (LOCK) mode
   	Secondary HO2S (Sensor 2) 4P connector: disconnected
   	PCM connector No. 1 (96P): disconnected
   Test point 1	Secondary HO2S (Sensor 2) 4P connector (female terminals) No. 2:
   Test point 2	PCM connector No. 1 (96P) No. 22

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

   Is there continuity?

   YES 

   The SO2 wire is OK. Go to step 4.

   NO 

   Repair an open in the SO2 wire between PCM connector No. 1 terminal No. 22 and secondary HO2S (Sensor 2).

4. Open wire check (SO2SG line)

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

   Test condition	Vehicle OFF (LOCK) mode
   	Secondary HO2S (Sensor 2) 4P connector: disconnected
   	PCM connector No. 1 (96P): disconnected
   Test point 1	Secondary HO2S (Sensor 2) 4P connector (female terminals) No. 1:
   Test point 2	PCM connector No. 1 (96P) No. 24

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

   Is there continuity?

   YES 

   The SO2SG wire is OK. Replace secondary HO2S (Sensor 2) .

   NO 

   Repair an open in the SO2SG wire between PCM connector No. 1 terminal No. 24 and secondary HO2S (Sensor 2).