DTC P144C: Open in Secondary Air Injection System Heater Control Circuit; DTC P144D: Short in Secondary Air Injection System Heater Control Circuit [08/2015 - 08/2019]: Procedure

1. Inspect the air pump heater relay (AIR PUMP HTR) (Refer to ON-VEHICLE INSPECTION [08/2015 - 08/2019] ).

Result: 

NG 

REPLACE AIR PUMP HEATER RELAY (AIR PUMP HTR) 

Result: 

OK 

See step  2

1. Remove the air pump heater relay (AIR PUMP HTR).
2. Measure the voltage according to the value(s) in the table below.

   Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

   Standard Voltage

   Tester Connection	Condition	Specified Condition
   Air pump heater relay terminal 2 - Body ground	Ignition switch ON	11 to 14 V

   TEXT IN ILLUSTRATION
   
   

   *1	Air Pump Heater Relay (AIR PUMP HTR)
   *2	Engine Room Relay Block

3. Reinstall the air pump heater relay (AIR PUMP HTR).

Result: 

NG 

See step  4

Result: 

OK 

See step  3

1. Remove the Air pump heater relay (AIR PUMP HTR).
2. Disconnect the ECM connector.
3. Measure the resistance according to the value(s) in the table below.

   Standard Resistance (Check for Open)

   Tester Connection	Condition	Specified Condition
   Air pump heater relay (AIR PUMP HTR) terminal 1 - C38-20 (HAI1)	Always	Below 1 Ω

   Standard Resistance (Check for Short)

   Tester Connection	Condition	Specified Condition
   Air pump heater relay (AIR PUMP HTR) terminal 1 or C38-20 (HAI1) - Body ground	Always	10 kΩ or higher

4. Reinstall the Air pump heater relay (AIR PUMP HTR).
5. Reconnect the ECM connector.

Result: 

OK 

REPLACE ECM 

(Refer to REMOVAL [08/2015 - ] )

Result: 

NG 

REPAIR OR REPLACE HARNESS OR CONNECTOR 

1. Remove the Air pump heater relay (AIR PUMP HTR).
2. Disconnect the air injection control driver connector.
3. Measure the resistance according to the value(s) in the table below.

   Standard Resistance (Check for Open)

   Tester Connection	Condition	Specified Condition
   Air pump heater relay (AIR PUMP HTR) terminal 2 - A45-5 (+B)	Always	Below 1 Ω

   Standard Resistance (Check for Short)

   Tester Connection	Condition	Specified Condition
   Air pump heater relay (AIR PUMP HTR) terminal 2 or A45-5 (+B) - Body ground	Always	10 kΩ or higher

4. Reinstall the Air pump heater relay (AIR PUMP HTR).
5. Reconnect the ECM connector.

Result: 

NG 

REPAIR OR REPLACE HARNESS OR CONNECTOR 

Result: 

OK 

See step  5

See step  1

Result: 

NG 

REPAIR OR REPLACE HARNESS OR CONNECTOR 

Result: 

OK 

See step  6

See step  2

Result: 

NG 

REPAIR OR REPLACE HARNESS OR CONNECTOR 

Result: 

OK 

See step  7

See step  3

Result: 

OK 

REPLACE AIR INJECTION CONTROL DRIVER 

(Refer to REMOVAL [08/2015 - ] )

Result: 

NG 

REPLACE ECM 

(Refer to REMOVAL [08/2015 - ] )