Last Modified: 7-3-2017 6.8:8.0.40 Doc ID: RM000001CTV004X
Model Year Start: 2007 Model: LX470 Prod Date Range: [08/2006 -           ]
Title: SUSPENSION CONTROL: ACTIVE HEIGHT CONTROL SUSPENSION: C1786/86; Height Control Switch Circuit; 2007 MY LX470 [08/2006 -        ]

DTC

C1786/86

Height Control Switch Circuit

DESCRIPTION

This circuit sending the signal to ECU in order to adjust the height to the aimed height select by the height select switch.

DTC No.

DTC Detection Condition

Trouble Area

C1786/86

Height select signal does not change
  • Suspension control switch (Height select switch)
  • Suspension control ECU
  • Wire harness

WIRING DIAGRAM

INSPECTION PROCEDURE

HINT:

When using the intelligent tester, start from *1. When not using the intelligent tester, start from *2.

PROCEDURE

1.

READ VALUE USING INTELLIGENT TESTER (HEIGHT SELECT SWITCH)*1

(a) Connect the intelligent tester (with CAN VIM) to the DLC3.

(b) Turn the ignition switch ON and push the intelligent tester main switch ON.

(c) Select the DATA LIST mode on the intelligent tester.

(d) Check the height select switch condition displayed on the intelligent tester when pushing UP and DOWN button of the height select switch.

OK:

When UP button is pushed: ON is displayed for height select up switch condition.

When DOWN button is pushed: ON is displayed for height select down switch condition.

NG

GO TO STEP 3

OK

REPLACE SUSPENSION CONTROL ECU

2.

CHECK SUSPENSION CONTROL ECU*2

(a) Remove the suspension control ECU with connectors still connected.

(b) Turn the ignition switch ON.

(c) Measure the voltage between terminals DNSW and UPSW of the suspension control ECU connector and body ground when DOWN and UP button of the height select switch is pushed.

Standard voltage:

Tester Connection

Condition

Specified Condition

S7-7 (DNSW) - Body ground

DOWN button pushed

9 to 14 V

S7-7 (DNSW) - Body ground

UP button pushed

Below 1.5 V

S7-8 (UPSW) - Body ground

UP button pushed

9 to 14 V

S7-8 (UPSW) - Body ground

DOWN button pushed

Below 1.5 V
NG

REPLACE SUSPENSION CONTROL ECU

OK

3.

INSPECT SUSPENSION CONTROL SWITCH (HEIGHT SELECT SWITCH)

(a) Remove the suspension control switch.

(b) Disconnect the suspension control switch (for height select switch) connector.

(c) Measure the resistance between terminals 6, 10 and 4 of suspension control switch (for height select switch) connector when UP and DOWN button of the height select switch is pushed.

Standard resistance:

Tester Connection

Condition

Specified Condition

6 - 4

UP button pushed

Below 1 Ω

6 - 4

DOWN button pushed

10 kΩ or higher

10 - 4

DOWN button pushed

Below 1 Ω

10 - 4

UP button pushed

10 kΩ or higher
NG

REPLACE SUSPENSION CONTROL SWITCH (HEIGHT SELECT SWITCH)

OK

4.

CHECK WIRE HARNESS (SUSPENSION CONTROL SWITCH (HEIGHT SELECT SWITCH) - SUSPENSION CONTROL ECU)
NG

REPAIR OR REPLACE HARNESS AND CONNECTOR

OK

REPLACE SUSPENSION CONTROL ECU