DTC C1793: Height Control Off Switch Circuit [08/2015 - 08/2019]: Procedure

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

   Tester Display	Measurement Item/Range	Normal Condition	Diagnostic Note
   Manual Mode Switch	Height control mode select switch (Manual)/ ON or OFF	ON: Height control mode select switch ON condition OFF: Height control mode select switch OFF condition	-

5. Check that the value displayed on the Techstream changes by pressing the height control mode select switch.

   OK

   Height control mode select switch value changes.

   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 PROBLEM SYMPTOMS TABLE [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. Remove the height control mode select switch.

   Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

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

   Standard Resistance

   Tester Connection	Switch Condition	Specified Condition
   3 - 6	Free	10 kΩ or higher
   3 - 6	Pushed in	Below 1 Ω

Result: 

NG 

REPLACE NO. 2 ABSORBER CONTROL SWITCH 

Result: 

OK 

See step  3

1. Disconnect the O16 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
   H73-6 - O16-13 (TD)	Always	Below 1 Ω
   H73-3 - Body ground	Always	Below 1 Ω
   H73-6 or O16-13 (TD) - Body ground	Always	10 kΩ or higher

Result: 

OK 

REPLACE SUSPENSION CONTROL ECU 

(Refer to REMOVAL [08/2015 - ] )

Result: 

NG 

REPAIR OR REPLACE HARNESS OR CONNECTOR