DTC C1747: Leveling Solenoid Valve Circuit Malfunction [08/2015 - 08/2019]: Procedure

1. Connect the Techstream to the DLC3.
2. Turn the ignition switch to ON, and turn the Techstream main switch on.
3. Enter the following menus: Chassis / Air suspension / Active Test.
   AIR SUSPENSION
   
   

   Tester Display	Test Part	Control Range	Diagnostic Note
   Rear Leveling Solenoid	Leveling solenoid valve	ON or OFF	Operation sound of solenoid (clicking sound) can be heard

   OK

   Operation of solenoid (clicking sound) can be heard

   RESULT
   
   

   Result	Proceed to
   NG	A
   OK (When troubleshooting according to the Problem Symptoms Table)	B
   OK (When troubleshooting according to the DTC Chart)	C

Result: 

B 

PROCEED TO NEXT CIRCUIT INSPECTION SHOWN IN PROBLEM SYMPTOMS TABLE 

(Refer to HOW TO PROCEED WITH TROUBLESHOOTING [08/2015 - ] )

Result: 

C 

USE SIMULATION METHOD TO CHECK 

(Refer to HOW TO PROCEED WITH TROUBLESHOOTING [08/2015 - 08/2017] , or refer to HOW TO PROCEED WITH TROUBLESHOOTING [08/2017 - 08/2018] , or refer to HOW TO PROCEED WITH TROUBLESHOOTING [08/2018 - 08/2019] )

Result: 

A 

See step  2

1. Turn the ignition switch off.
2. Disconnect Q4 solenoid valve connector.

   Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

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

   Standard Resistance

   Tester Connection	Condition	Specified Condition
   2 (E) - 3 (RH+)	20°C (68°F)	10 to 14 Ω

4. Connect the battery positive (+) lead to terminal 3 (RH+) and the negative (-) lead to terminal 2 (E) of the solenoid valve connector. Then check that the valve makes an operating sound.

   OK

   Operation of solenoid (clicking sound) can be heard

Result: 

NG 

REPLACE NO. 2 HEIGHT CONTROL VALVE SUB-ASSEMBLY 

(Refer to REMOVAL [08/2015 - ] )

Result: 

OK 

See step  3

1. Disconnect the O17 ECU connector.

   Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

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

   Standard Resistance

   Tester Connection	Condition	Specified Condition
   Q4-3 (RH+) - O17-16 (SLRR)	Always	Below 1 Ω
   Q4-3 (RH+) or O17-16 (SLRR) - Body ground	Always	10 kΩ or higher
   Q4-2 (E) - Body ground	Always	Below 1 Ω

Result: 

OK 

REPLACE SUSPENSION CONTROL ECU 

(Refer to REMOVAL [08/2015 - ] )

Result: 

NG 

REPAIR OR REPLACE HARNESS OR CONNECTOR