DTC P144C: Open in Secondary Air Injection System Heater Control Circuit; DTC P144D: Short in Secondary Air Injection System Heater Control Circuit [08/2015 - 08/2017]: Procedure
WARNING: This page is about a different car, the 2018 Toyota Sequoia, 2017 Toyota Sequoia, and 2016 Toyota Sequoia. However, it is still accessible from the selected car via links, so may be relevant.
- INSPECT AIR PUMP HEATER RELAY (AI-HTR)
- Inspect the air pump heater relay (AI-HTR) (Refer to PROCEDURE - Step 7 ).
Result:
NG
REPLACE AIR PUMP HEATER RELAY (AI-HTR)
Result:
OK
See step 2
- CHECK AIR PUMP HEATER RELAY (AI-HTR) (POWER SOURCE)
- Remove the air pump heater relay (AI-HTR).
- Measure the voltage according to the value(s) in the table below.
Standard Voltage
Tester Connection Condition Specified Condition AI-HTR relay terminal 1 - Body ground Ignition switch ON 11 to 14 V
Result:
NG
REPAIR OR REPLACE HARNESS OR CONNECTOR
Result:
OK
See step 3
- CHECK HARNESS AND CONNECTOR (ECM - AI-HTR RELAY)
- Remove the air pump heater relay (AI-HTR).
- Disconnect the ECM connector.
- Measure the resistance according to the value(s) in the table below.
Standard Resistance
Tester Connection Condition Specified Condition AI-HTR relay terminal 2 - D56-61 (HAI1) Always Below 1 Ω AI-HTR relay terminal 2 or D56-61 (HAI1) - Body ground Always 10 kΩ or higher
Result:
OK
REPLACE ECM
(Refer to REMOVAL [08/2015 - 08/2018] )
Result:
NG
REPAIR OR REPLACE HARNESS OR CONNECTOR