Last Modified: 11-29-2007 1.6 C
Service Category: Suspension Section: Suspension Control System
Model Year: 2008 Model: Sequoia Doc ID: RM000001N93008X
Title: SUSPENSION CONTROL: AIR SUSPENSION SYSTEM (w/o AVS): DESCRIPTION (2008 Sequoia)

DTC

C1782

Power Source Voltage Malfunction

DESCRIPTION

  • This circuit provides power to operate the suspension control ECU.
  • The suspension control ECU, controlling the air suspension system, is activated when the ignition switch is turned ON. The main relay inside the ECU is activated after 2 seconds and the system is operated by +B power source.

DTC Code

Detection Condition

Trouble Area

C1782

Terminal IG, B or BAT voltage is 10 V or less, or 16 V or more for 0.5 seconds
  • Battery
  • Wire harness or connector
  • Suspension control ECU

WIRING DIAGRAM

INSPECTION PROCEDURE

PROCEDURE

1.

READ VALUE USING TECHSTREAM (POWER SOURCE VOLTAGE)

(a) Connect the Techstream to the DLC3.

(b) Turn the ignition switch to ON, and turn the Techstream main switch on.

(c) Enter the following menus: Chassis / Air suspension / Data List.

Air Suspension

Tester Display

Measurement Item/Range

Normal Condition

Diagnostic Note

+B Power Source Voltage

ECU power supply voltage / min.: 0 V, max.: 25.5 V

Actual battery power supply voltage: 11 to 14 V

-

IG Power Source Voltage

ECU power supply voltage / min.: 0 V, max.: 25.5 V

Actual ECU power supply voltage: 11 to 14 V

-

Standard voltage:

11 to 14 V

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
A

2.

INSPECT FUSE (AIR SUS, AIR SUS NO. 2, ECU-IG NO. 2)

(a) Remove the AIR SUS No. 2 and AIR SUS fuses from the engine room relay block.

(b) Remove the ECU-IG No. 2 fuse from the cowl side junction block LH.

(c) Measure the resistance of the AIR SUS, AIR SUS No. 2 and ECU-IG No. 2 fuses.

Standard Resistance:

Fuse

Condition

Specified Condition

AIR SUS No. 2

Always

Below 1 Ω

AIR SUS

Always

Below 1 Ω

ECU-IG No. 2

Always

Below 1 Ω

(d) Reinstall the AIR SUS, AIR SUS No. 2 and ECU-IG No. 2 fuses.

OK

3.

CHECK BATTERY VOLTAGE

(a) Disconnect the O19 ECU connector.

(b) Measure the voltage according to the value(s) in the table below.

Standard Voltage:

Tester Connection

Switch Condition

Specified Condition

O19-24 (B) - Body ground

Always

11 to 14 V

O19-25 (BAT) - Body ground

Always

11 to 14 V

O19-10 (IG) - Body ground

Ignition switch ON

11 to 14 V
OK

4.

CHECK FOR DTC

(a) Clear the DTC SUSPENSION CONTROL: AIR SUSPENSION SYSTEM (w/o AVS): DTC CHECK / CLEAR (2008 Sequoia) .

(b) Check for DTC SUSPENSION CONTROL: AIR SUSPENSION SYSTEM (w/o AVS): DTC CHECK / CLEAR (2008 Sequoia) .

Result

Result

Proceed to

DTC is not output

A

DTC is output

B
A