Air Suspension System

SUSPENSION CONTROL: AIR SUSPENSION SYSTEM: C1715/15-C1717/17,C1796/96-C1798/98: Front Acceleration Sensor RH Malfunction
C1798/98 - (Up & Down) G Sensor Rear

DESCRIPTION

The acceleration sensor (up and down G sensor) detects the upward and downward acceleration of the vehicle, and outputs it as a voltage to the suspension control ECU. Up and down G sensors are installed in 3 locations: 1) the suspension control ECU, 2) the RH side instrument panel, and 3) behind the deck trim side panel assembly LH. Each up and down G sensor independently detects the upward and downward acceleration. During a test mode inspection, the suspension control ECU reads the fluctuations in each sensor signal. If a sensor signal does not fluctuate, test mode DTCs C1796/96, C1797/97 and C1798/98 are stored.





HINT
If DTCs C1716/16 and C1797/97 are output, replace the suspension control ECU (houses the front acceleration sensor LH).

WIRING DIAGRAM





INSPECTION PROCEDURE

NOTICE:
When replacing the suspension control ECU, perform registration Testing and Inspection.

PROCEDURE

1. READ VALUE USING TECHSTREAM (G SENSOR)

(a) Turn the engine switch off.

(b) Connect the Techstream to the DLC3.

(c) Turn the engine switch on (IG).

(d) Turn the Techstream on.

(e) Enter the following menus: Chassis / Air suspension / Data List.

Air Suspension





OK:

Acceleration value changes.

NG -- INSPECT ACCELERATION SENSOR (FRONT RH OR REAR)

OK -- USE SIMULATION METHOD TO CHECK How To Proceed With Troubleshooting

2. INSPECT ACCELERATION SENSOR (FRONT RH OR REAR)





(a) Check the front acceleration sensor RH (when DTC C1715/15 or C1796/96 is output).

(1) Remove the front acceleration sensor RH Removal.

(2) Connect 3 dry cell batteries of 1.5 V in series.

(3) Connect the positive (+) end of the batteries to terminal 3 (SHB) of the acceleration sensor and the negative (-) end of the batteries to terminal 2 (SHG). Then measure the voltage between terminal 1 (SGFL) and terminal 2 (SHG).

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

Standard Voltage:





Text in Illustration





(b) Check the rear acceleration sensor: (when DTC C1717/17 or C1798/98 is output).

(1) Remove the rear acceleration sensor Removal.

(2) Connect 3 dry cell batteries of 1.5 V in series.

(3) Connect the positive (+) end of the batteries to terminal 3 (SGV) of the acceleration sensor and the negative (-) end of the batteries to terminal 2 (SGND). Then measure the voltage between terminal 1 (SGRR) and terminal 2 (SGND).

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

Standard Voltage:





NOTICE:
Do not apply a voltage of higher than 6 V.

HINT
When the acceleration sensor is tilted, it may output a different value.

Result





C -- REPLACE REAR ACCELERATION SENSOR Removal

B -- REPLACE FRONT ACCELERATION SENSOR RH Removal
A -- Continue to next step.

3. CHECK HARNESS AND CONNECTOR (ACCELERATION SENSOR - SUSPENSION CONTROL ECU)

(a) Check the front acceleration sensor RH (when DTC C1715/15 or C1796/96 is output).

(1) Disconnect the A10 front acceleration sensor RH connector.

(2) Disconnect the A11 suspension control ECU connector.

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

Standard Resistance:





(b) Check the rear acceleration sensor: (when DTC C1717/17 or C1798/98 is output).

(1) Disconnect the R21 rear acceleration sensor connector.

(2) Disconnect the A40 suspension control ECU connector.

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

Standard Resistance:





NG -- REPAIR OR REPLACE HARNESS OR CONNECTOR

OK -- REPLACE SUSPENSION CONTROL ECU Removal