The following warning indicates a possible problem in the brake system.
Immediately stop the vehicle in a safe place and contact your Toyota dealer.

If a warning light turns on or a warning buzzer sounds...
Stop the vehicle immediately.Vehicle Speed Sensor "A" Intermittent / Erratic / High (P0503)
DESCRIPTION
If a malfunction (a rapid change in vehicle speed) in the vehicle speed signal
being output from the skid control ECU is detected while the cruise control is in
operation, the ECM determines that there is a momentary interruption or noise, and ...
Removal
REMOVAL
PROCEDURE
1. REMOVE UPPER BACK WINDOW PANEL TRIM
2. REMOVE BACK DOOR PANEL TRIM ASSEMBLY
3. DISCONNECT POWER BACK DOOR ROD (w/ Power Back Door)
4. REMOVE BACK DOOR TRIM COVER LH (w/o Power Back Door)
5. REMOVE BACK DOOR TRIM COVER LH ...
How To Proceed With Troubleshooting
CAUTION / NOTICE / HINT
HINT:
Use the following procedure to troubleshoot the air conditioning system.
*: Use the Techstream.
PROCEDURE
1.
VEHICLE BROUGHT TO WORKSHOP
NEXT
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