DTC P0138: Inspection

SO2, SO2_SG [SO2SG] Circuit Inspection 

Test Procedure 

• Preparation
  1. -

     Secondary HO2S (Sensor 2) connector (4P): disconnected

  2. -

     PCM connector A (50P): disconnected

• Procedure
  1. -

     Perform the inspection according to the following chart.

			(Disconnected) Secondary HO2S (Sensor 2) connector (4P) female terminals	(Disconnected) PCM connector A (50P) female terminals
		IG Mode	Courtesy of HONDA, U.S.A., INC.	Courtesy of HONDA, U.S.A., INC.	Normal Conditions
	SO2 open wire inspection	OFF			There is less than 1 Ohm
	SO2_SG [SO2SG] open wire inspection	OFF			There is less than 1 Ohm
	Refer to the Open/Shorted Wire Inspection Description for the method to inspect the shorted circuit below, then start to inspect according to circumstances.
	SO2_SG [SO2SG] shorted to power inspection	ON			There is less than about 5 V

Results 

• If abnormal, there is a problem in the circuit.

PCM Inspection 

Preconditions 

• External circuit is normal

Test Procedure 

Unit output voltage inspection

• Preparation
  1. -

     Secondary HO2S (Sensor 2) connector (4P): disconnected

• Procedure
  1. Jump the secondary HO2S (Sensor 2) connector (4P) terminals No. 1 and No. 2 with a jumper wire.
  2. Turn the vehicle to the ON mode.
  3. Confirm the HDS [HO2S S2].

	(Disconnected) Secondary HO2S (Sensor 2) connector (4P) female terminals
	Courtesy of HONDA, U.S.A., INC.

• Normal Conditions
  1. -

     HDS [HO2S S2] value is less than 3.28 V  .

Results 

• If it is abnormal, there is a problem with the PCM.

Secondary HO2S (Sensor 2) Inspection 

Test Procedure 

• If the other inspection item(s) indicated a normal condition, then it is determined that remaining secondary HO2S (Sensor 2) is the cause.

Results 

• There is a problem with secondary HO2S (Sensor 2).