Inspection Procedure

NOTE:

Before performing troubleshooting, inspect the connectors of related circuits.
Before replacing the suspension control ECU, perform all of the following again: 1) symptom simulation (see ELECTRONIC CIRCUIT INSPECTION PROCEDURE ); 2) DTC inspection; and 3) Intelligent tester or Techstream inspection (Data List or Active Test). If no malfunctions are found in other areas, replace the suspension control ECU.
If the suspension control ECU or height control sensor is replaced, the vehicle height offset calibration must be performed (see INITIALIZATION ).

CHECK IG VOLTAGE (DATA LIST)

Turn the engine switch off.
Connect the Intelligent tester or Techstream to the DLC3.
Turn the engine switch on (IG) and turn the tester ON.
Enter the following menus:
1. Intelligent tester - Select: DIAGNOSIS / OBD/MOBD / CHASSIS / AIR SUSPENSION I DATA LIST /
2. Techstream - Select: Chassis / Air suspension / Data List /

Check the values by referring to the table below.

Intelligent tester

AIR SUSPENSION

INTELLIGENT TESTER - AIR SUSPENSION SPECIFICATION

Tester Display	Measurement Item/Range	Normal Condition	Diagnostic Note
IG VOLTAGE	ECU power supply voltage/ min.: 0 V max.: 255 V	Engine switch on (IG): 11 to 14 V	-

Techstream

Air suspension

TECHSTREAM - AIR SUSPENSION SPECIFICATION

Tester Display	Measurement Item/Range	Normal Condition	Diagnostic Note
IG Power source Voltage	ECU power supply voltage/ min.:0V max.: 255 V	Engine switch on (IG): 11 to 14 V	-

OK: 11 to 14 V

Result

RESULT CHART

Result	Proceed to
NG	A
OK	B

B: PROCEED TO NEXT CIRCUIT INSPECTION SHOWN IN PROBLEM SYMPTOMS TABLE (See PROBLEM SYMPTOMS TABLE )

A: GO TO NEXT STEP

INSPECT FUSE (AIRSUS)

Remove the AIRSUS fuse from the passenger side junction block.

Measure the resistance of the fuse.

Standard resistance

FUSE (AIRSUS)

Tester Connection	Condition	Specified Condition
AIRSUS fuse	Always	Below 1 Ω

NG: Go to step 7

OK: GO TO NEXT STEP

INSPECT PASSENGER SIDE JUNCTION BLOCK (AIRSUS RELAY)

Disconnect the L88 ECU connector.

Measure the voltage according to the value(s) in the table below.

Standard voltage

PASSENGER SIDE JUNCTION BLOCK (AIRSUS RELAY)

Tester Connection	Switch Condition	Specified Condition
L88-1 (B) - L88-4 (GND)	Engine switch on (IG)	11 to 14 V

Fig 1: Inspecting Passenger Side Junction Block (Airsus Relay)

Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

Result

RESULT CHART

Result	Proceed to
NG	A
OK	B

B: REPLACE SUSPENSION CONTROL ECU (See REMOVAL )

A: GO TO NEXT STEP

CHECK HARNESS AND CONNECTOR (PASSENGER SIDE JUNCTION BLOCK - ECU AND BODY GROUND)

Disconnect the L88 ECU connector.
Disconnect the PA passenger side junction block connector.

Measure the resistance according to the value in the table below.

Standard resistance

PASSENGER SIDE JUNCTION BLOCK - ECU AND BODY GROUND

Tester Connection	Condition	Specified Condition
L88-1 (B) - PA-44	Always	Below 1 Ω
L88-4 (GND) - Body ground	Always	Below 1 Ω

Fig 2: Checking Harness And Connector (Passenger Side Junction Block - ECU And Body Ground)

Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

NG: REPAIR OR REPLACE HARNESS OR CONNECTOR

OK: GO TO NEXT STEP

CHECK HARNESS AND CONNECTOR (BATTERY - PASSENGER SIDE JUNCTION BLOCK)

Disconnect the PL junction block connector.

Measure the voltage according to the value(s) in the table below.

Standard voltage

BATTERY - PASSENGER SIDE JUNCTION BLOCK

Tester Connection	Condition	Specified Condition
PL-1 - Body ground	Always	11 to 14 V

Fig 3: Checking Harness And Connector (Battery - Passenger Side Junction Block)

Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

NG: REPAIR OR REPLACE HARNESS OR CONNECTOR

OK: GO TO NEXT STEP

CHECK HARNESS AND CONNECTOR (MAIN BODY ECU - JUNCTION BLOCK AND BODY GROUND)

Disconnect the PA junction block connector.

Measure the voltage and resistance according to the value(s) in the table below.

Standard voltage

MAIN BODY ECU - JUNCTION BLOCK AND BODY GROUND VOLTAGE

Tester Connection	Switch Condition	Specified Condition
PA-15 - Body ground	Engine switch on (IG)	11 to 14 V

Fig 4: Checking Harness And Connector (Main Body ECU - Junction Block And Body Ground)

Standard resistance

MAIN BODY ECU - JUNCTION BLOCK AND BODY GROUND RESISTANCE

Tester Connection	Condition	Specified Condition
PA-39 - Body ground	Always	Below 1 Ω

NG: REPAIR OR REPLACE HARNESS OR CONNECTOR

OK: GO TO NEXT STEP

CHECK HARNESS AND CONNECTOR (PASSENGER SIDE JUNCTION BLOCK - ECU)

Disconnect the L88 ECU connector.
Connect the PA passenger side junction block connector.

Measure the resistance according to the value in the table below.

Standard resistance

PASSENGER SIDE JUNCTION BLOCK - ECU

Tester Connection	Condition	Specified Condition
L88-1 (B) - Body ground	Always	10 kΩ or higher

Fig 5: Checking Harness And Connector (Passenger Side Junction Block - ECU)

HINT:

If the fuse is blown, replace the fuse.

NG: REPAIR OR REPLACE HARNESS OR CONNECTOR

OK: REPLACE PASSENGER SIDE JUNCTION BLOCK