DTC C1794: Height Control OFF Switch Circuit (Test Mode DTC) (FROM 08/2009): Procedure

1. Disconnect the height control OFF switch connector.
   Fig 1: Inspecting Height Control Off Switch

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2. Measure the resistance according to the values in the table below.

   Standard resistance

   Tester Connection	Condition	Specified Condition
   2 (MSW) - 1 (E)	Height control OFF switch while pressing button	Below 1 Ω
   	Neutral position	10 kΩ or higher

   TEXT IN ILLUSTRATION
   
   

   *1	Component without harness connected (Height Control OFF Switch)

NG → See step   4 

OK: Go to next step 

1. Disconnect the A56 ECU connector.
   Fig 2: Identifying A56 ECU Connector

   Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
2. Disconnect the F18 height control OFF switch connector.
3. Measure the resistance according to the values in the table below.

   Standard resistance

   Tester Connection	Condition	Specified Condition
   F18-2 (MSW) - A56-13 (TD)	Always	Below 1 Ω
   A56-13 (TD) - Body ground	Always	10 kΩ or higher

   TEXT IN ILLUSTRATION
   
   

   *1	Front view of wire harness connector (to Height Control Switch)
   *2	Rear view of wire harness connector (to Suspension Control ECU)

NG → REPAIR OR REPLACE HARNESS OR CONNECTOR 

OK → See step   3