Air Suspension - Diagnostic Trouble Code Checking
SUSPENSIONSU95-001
FEBRUARY 17, 1995
LS 400 (W/AIR SUSPENSION)
The Air Suspension Diagnostic Trouble Code Checking and Canceling Procedures listed on pages SA-92 and SA-93 in the '95 LS 400 Repair Manual (Pub. No. RM405U1) are incorrect.
This bulletin contains the correct procedures for reading and clearing the Diagnostic Trouble Codes from the Electronic Air Suspension on the 1995 LS 400. In general, the correct procedure differs from the Repair Manual in the following areas:
1. The DOME-FR fuse must be removed prior to checking trouble codes.
2. Trouble codes can be canceled by simply shorting Tc to E1 and turning on the ignition switch for 5 seconds with the DOME-FR fuse installed.
Do not follow the instructions in the 1995 LS 400 Repair Manual. This procedure may result in the inadvertent erasing of stored trouble codes before they can be retrieved.
CHECKING DIAGNOSTIC TROUBLE CODES
1. Remove the DOME-FR fuse in the engine compartment fuse box.
Notice:
Removing the DOME-FR fuse cuts off the backup power to the seat memory and the clock. Before starting repairs, make a note of the power seat position. Before returning the vehicle to the customer, reset the power seat to the previously memorized position and reset the clock.
2. Open the driver's door.
3. Using the diagnostic check wiring SST, connect terminals Tc and E1 of the DLC1 or DLC2 (SST # 09843-18020).
4. Turn the ignition switch on.
5. Read the diagnostic trouble code output on the height control indicator
NOTE:
When the engine is not running, diagnostic trouble code "73" is indicated. This is normal.
When a diagnostic trouble code is not indicated, check the Tc terminal circuit.
Examples of the blinking patterns for normal condition and trouble codes 11 and 31 are shown in the illustrations.
6. Check the malfunction using the code table.
7. After completing the check, disconnect terminals Tc and E1 and turn off the display.
NOTE:
In the event of 2 or more malfunction codes, the smallest numbered code will be displayed first.
DIAGNOSTIC TROUBLE CODE CHECK BY USING LEXUS HANDHELD TESTER
1. Remove the DOME-FR fuse in the engine compartment box.
2. Hook up the Lexus hand-held tester to the DLC2.
3. Read the diagnostic trouble codes by following the prompts on the tester screen in 'air suspension mode'
Please refer to the Lexus Hand Held Tester Operator's Manual.
CANCELING DIAGNOSTIC TROUBLE CODES
1. Install the DOME-FR fuse to the engine compartment fuse box.
2. Using diagnostic check wiring SST, connect terminals Tc and E1 of DLC1 or DLC2 (SST# 09843-18020).
3. Turn the ignition switch on for 5 seconds or longer.