DTC C1792: Height Control Switch Circuit (Test Mode DTC) [08/2021 - ]: Procedure

1. Turn the engine switch off.
2. Connect the Techstream to the DLC3.
3. Turn the engine switch on (IG).
4. Turn the Techstream on.
5. Enter the following menus: Chassis / Air suspension / Data List.
   AIR SUSPENSION
   
   

   Tester Display	Measurement Item/Range	Normal Condition	Diagnostic Note
   Height Control Switch (UP)	Height control switch ("up" side) / ON or OFF	ON: Switch is pressed and held OFF: Switch is not pressed	-
   Height Control Switch (DOWN)	Height control switch ("down" side) / ON or OFF	ON: Switch is pressed and held OFF: Switch is not pressed	-

6. Check that the value displayed on the Techstream changes by pressing the height control switch (center cluster module switch RH) "up" side or "down" side.

   OK

   Height control switch (center cluster module switch RH) value changes.

   Result

   Result
   OK
   NG

Result: 

OK 

USE SIMULATION METHOD TO CHECK. Refer to  HOW TO PROCEED WITH TROUBLESHOOTING [08/2021 - 08/2022]  , or refer to  HOW TO PROCEED WITH TROUBLESHOOTING [08/2022 - ] 

Result: 

NG 

See step  2

1. Turn the engine switch off.
2. Remove the height control switch (center cluster module switch RH).

   Refer to REMOVAL [08/2021 - ]

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

   Standard Resistance

   Tester Connection	Switch Condition	Specified Condition
   8 (LO) - 10 (GND)	"Down" pressed	Below 1 Ω
   8 (LO) - 10 (GND)	"Up" pressed	10 kΩ or higher
   3 (HI) - 10 (GND)	"Down" pressed	10 kΩ or higher
   3 (HI) - 10 (GND)	"Up" pressed	Below 1 Ω

   Result

   Result
   OK
   NG

   Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

   *a	Component without harness connected (Height Control Switch [Center Cluster Module Switch RH])

Result: 

NG 

REPLACE HEIGHT CONTROL SWITCH (CENTER CLUSTER MODULE SWITCH RH). Refer to  REMOVAL [08/2021 - ] 

Result: 

OK 

See step  3

1. Disconnect the v3 height control switch (center cluster module switch RH) connector.
2. Disconnect the A40 suspension control ECU connector.
3. Measure the resistance according to the value(s) in the table below.

   Standard Resistance

   Tester Connection	Condition	Specified Condition
   v3-3 (HI) - A40-15 (UPSW)	Always	Below 1 Ω
   v3-8 (LO) - A40-14 (DNSW)	Always	Below 1 Ω
   v3-10 (GND) - Body ground	Always	Below 1 Ω
   v3-3 (HI) - Body ground	Always	10 kΩ or higher
   v3-8 (LO) - Body ground	Always	10 kΩ or higher

   Result

   Result
   OK
   NG

Result: 

OK 

REPLACE SUSPENSION CONTROL ECU. Refer to  REMOVAL [08/2015 - ] 

Result: 

NG 

REPAIR OR REPLACE HARNESS OR CONNECTOR