DTC C1794: Height Control OFF Switch Circuit (Test Mode DTC) [08/2019 - 08/2021]: Procedure

1. Remove the height control OFF switch (combination switch assembly).

   Refer to REMOVAL [08/2015 - 08/2021]

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

   Standard Resistance

   Tester Connection	Switch Condition	Specified Condition
   16 (N) - 9 (E)	Height control OFF switch (combination switch assembly) pressed	Below 1 Ω
   	Height control OFF switch (combination switch assembly) not pressed	10 kΩ or higher

   Result

   Result
   OK
   NG

   Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

   *a	Component without harness connected (Height Control OFF Switch [Combination Switch Assembly])

Result: 

NG 

REPLACE HEIGHT CONTROL OFF SWITCH (COMBINATION SWITCH ASSEMBLY). Refer to  REMOVAL [08/2015 - 08/2021] 

Result: 

OK 

See step  2

1. Disconnect the A40 suspension control ECU connector.
2. Disconnect the i5 height control OFF switch (combination switch assembly) connector.
3. Measure the resistance according to the value(s) in the table below.

   Standard Resistance

   Tester Connection	Condition	Specified Condition
   A40-13 (TD) - i5-16 (N)	Always	Below 1 Ω
   A40-13 (TD) - Body ground	Always	10 kΩ or higher
   i5-9 (E) - Body ground	Always	Below 1 Ω

   Result

   Result
   OK
   NG

Result: 

OK 

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

Result: 

NG 

REPAIR OR REPLACE HARNESS OR CONNECTOR