Inspection Procedure

WARNING: This page is about a different car, the 2007 Toyota Tacoma. However, it is still accessible from the selected car via links, so may be relevant.

HINT:

Diagnostic information output by the AID can be confirmed by connecting an oscilloscope to the diagnostic information terminal of the AID. Reading the waveform while performing the AIR system intrusive operation provided in the SYSTEM CHECK function, allows the possible trouble areas to be narrowed down.

Start the engine and warm it up.
Turn the ignition switch to OFF.
Connect an intelligent tester to the DLC3.
Connect oscilloscope probes to the AIDI and E1 terminals of the ECM.

Fig 1: Connecting Oscilloscope Probes To AIDI And E1 Terminals Of ECM
Courtesy of TOYOTA MOTOR SALES, U.S.A., INC.
Turn the ignition switch to ON and turn the tester ON.
Select the following menu items: DIAGNOSIS / ENHANCED OBD II / SYSTEM CHECK / AIR INJ CHECK / MANUAL OPERATION / AP: ON, ASV: OPEN and AP: OFF, ASV CLOSE.
HINT:

When MANUAL OPERATION is selected, the tester initialization (atmospheric pressure measurement) is performed automatically. The initialization takes 10 seconds. After the initialization, AP and ASV operation can be selected.
Start the engine.
Perform the AIR system intrusive operation while the engine is idling.

Fig 2: Identifying Intelligent Tester Display
Courtesy of TOYOTA MOTOR SALES, U.S.A., INC.

Monitor the AID voltage output (duty ratio signal).

Fig 3: Identifying Aid Voltage Output (Duty Ratio Signal)

Courtesy of TOYOTA MOTOR SALES, U.S.A., INC.

Oscilloscope range

OSCILLOSCOPE RANGE

Items	Contents
Terminals	CH1: AIDI - E1
Equipment Settings	5 V/Division, 20 to 50 ms/Division
Conditions	Idling

Turn the ignition switch to OFF.

Fig 4: Identifying Intelligent Tester Display
Courtesy of TOYOTA MOTOR SALES, U.S.A., INC.

NOTE:

This AIR INJECTION CHECK only allows technicians to operate the AIR system for a maximum of 5 seconds. Furthermore, the check can only be performed up to 4 times per trip. If the test is repeated, intervals of at least 30 seconds are required between checks. While AIR system operation using the intelligent tester is prohibited, the tester display indicates the prohibition (WAIT or ERROR).
If an ERROR as shown in the illustration is displayed on the tester during the test, stop the engine for 10 minutes, and then try again.
Performing the AIR INJ CHECK repetitively may cause damage to the AIR system. If necessary, leave an interval of several minutes between SYSTEM CHECK operations to prevent the system from overheating.
When performing the AIR INJ CHECK operation after the battery cable has been reconnected, wait for 7 minutes with the ignition switch turned to ON or the engine running.
Turn the ignition switch to OFF when the AIR INJ CHECK operation finishes.

OSCILLOSCOPE RANGE

AID Diagnostic Signal Waveforms	ECM Commands	DTCs (ECM Output)	Suspected Trouble Areas
100% Duty Ratio See 1 waveform 1	Any Air Injection (AIR) System operation	P1613	Open in diagnostic signal circuit Air Injection Control Driver (AID) Open in AID +B circuit (AID power source) Short between +B and diagnostic signal circuits
0 % Duty Ratio See 2 waveform 2	AIR System: ON (Air pump ON, ASV ON)	P1613	Open or short in air pump or Air Switching Valve (ASV) command signal circuit (ECM-AID) Open in AID ground circuit Short between diagnostic signal circuit and body ground AID ECM
0 % Duty Ratio See 2 waveform 2	AIR System: OFF (Air pump OFF, ASV OFF)	-	Normal
20 % Duty Ratio See 3 waveform 3	Air Pump: ON	P0418	Short between air pump drive circuit and body ground Harness and connector (AID-Pump) Air pump AID ECM
20 % Duty Ratio See 3 waveform 3	Air Pump: OFF	P0418	Open in air pump drive circuit (AID-Pump), or short between air pump drive circuit and +B Harness and connector (AID-Pump) Air pump AID ECM
40 % Duty Ratio See 4 waveform 4	ASV: ON	P0412	Short between ASV drive circuit and body ground Harness and connector (AID-ASV) ASV AID ECM
40 % Duty Ratio See 4 waveform 4	ASV: OFF	P0412	Open in ASV drive circuit (AID-ASV), or short between ASV drive circuit and +B Harness and connector (AID-ASV) AID ASV ECM
80 % Duty Ratio See 5 waveform 5	AIR System: OFF (Air pump OFF, ASV OFF)	P1613	AID ECM
80 % Duty Ratio See 5 waveform 5	AIR System: ON (Air pump ON, ASV ON)	-	Normal
Other than above (other than 0, 20, 40, 80 and 100 % duty)	-	P1613	AID Open in AID ground circuit

Waveform 1
100 % Duty Ratio

Fig 5: Waveform Graph (Waveform 1)
Courtesy of TOYOTA MOTOR SALES, U.S.A., INC.
Waveform 2
0 % Duty Ratio

Fig 6: Waveform Graph (Waveform 2)
Courtesy of TOYOTA MOTOR SALES, U.S.A., INC.
Waveform 3
20 % Duty Ratio

Fig 7: Waveform Graph (Waveform 3)
Courtesy of TOYOTA MOTOR SALES, U.S.A., INC.
Waveform 4
40 % Duty Ratio

Fig 8: Waveform Graph (Waveform 4)
Courtesy of TOYOTA MOTOR SALES, U.S.A., INC.
Waveform 5
80 % Duty Ratio

Fig 9: Waveform Graph (Waveform 5)
Courtesy of TOYOTA MOTOR SALES, U.S.A., INC.

HINT:

By using an intelligent tester to perform the AIR INJ CHECK operation in the SYSTEM CHECK, the air-fuel ratio and the pressure in the secondary air injection system passage can be checked while the secondary air injection system is operating. This helps technicians to troubleshoot the system when it malfunctions.
Read freeze frame data using an intelligent tester. Freeze frame data record the engine condition when malfunctions are detected. When troubleshooting, freeze frame data can help determine if the vehicle was moving or stationary, if the engine was warmed up or not, if the air-fuel ratio was lean or rich, and other data, from the time the malfunction occurred.

INSPECT AIR PUMP ASSEMBLY

Disconnect the A9 air pump connector.

Measure the air pump resistance.

Standard Resistance

RESISTANCE REFERENCE CHART

Tester Connections	Specified Conditions
Air pump (A9-1) - Air pump (A9-2)	0.4 to 10 Ω at 20°C (68°F)

Reconnect the air pump connector.

Fig 10: Identifying Air Pump Connector Terminals

Courtesy of TOYOTA MOTOR SALES, U.S.A., INC.

NG: REPLACE AIR PUMP ASSEMBLY

OK: Go to Next Step

CHECK HARNESS AND CONNECTOR (AIR PUMP - BODY GROUND)

Disconnect the A9 air pump connector.

Check the resistance.

Standard Resistance

RESISTANCE REFERENCE CHART

Tester Connections	Specified Conditions
Air Pump (A9-1) - Body ground	Below 1 Ω

Reconnect the air pump connector.

Fig 11: Identifying A9 Air Pump Connector Terminals

Courtesy of TOYOTA MOTOR SALES, U.S.A., INC.

NG: REPAIR OR REPLACE HARNESS OR CONNECTOR

OK: Go to Next Step

CHECK HARNESS AND CONNECTOR (AIR PUMP - AIR INJECTION CONTROL DRIVER)

Disconnect the A9 air pump connector.
Disconnect the A6 AID connector.

Check the resistance.

Standard Resistance

RESISTANCE REFERENCE CHART

Tester Connections	Specified Conditions
Air Pump (A9-2) - AID (A6-2)	Below 1 Ω

Reconnect the air pump connector.
Reconnect the AID connector.

Fig 12: Identifying Harness And Connector (Air Pump - Air Injection Control Driver)

Courtesy of TOYOTA MOTOR SALES, U.S.A., INC.

NG: REPAIR OR REPLACE HARNESS OR CONNECTOR

OK : REPLACE AIR INJECTION CONTROL DRIVER