Toyota: Zero Point Calibration
Posted by Matthew Yu on Thu, Dec 17, 2009 @ 02:11 PM
Each and everyday vehicles are becoming more complex with electronics and computers to control what your vehicles does, how it moves, and every aspect in between. So scan tools have to meet those standard or repairs shops might as well be non-existent. An example of a job that's easier with a scan tool is Zero Point Calibration. Most Toyota's are equipped with a Vehicle Stability Control module (VSC) system that uses the information transmitted from your steering angle sensor that monitors the driver's steering inputs to
determine if the vehicle is responding the way the driver intends, so
accurate calibration is essential for the VSC system to
do its job.
You MUST perform the calibration procedure when any replacement or repairs of any steering related parts are
processed on the vehicle such as:
- Vehicle Stability Control module
- Steering Angle sensor
- Yaw Rate Sensor
- Deceleration Sensor
This procedure is relevant on 2004-'05 Toyota Camry, 4Runner, Highlander, RAV4, Sienna, Solara, Tundra, Land Cruiser, or Scion xB(Not all Scion are equipped with VSC). A reset also may be necessary if the wheels have been realigned, especially if the steering wheel was off-center due to a misalignment or unequal adjustments.
Below is the procedure to perform the Zero Point Calibration with screen shots from the AUTOBOSS V30 / PC Max scan tool:
1) Connect your scan tool to the car's DLC port
2) In Select Socket screen confirm which connector you are using to diagnose the vehicle
3) Select "Chassis" and click "ABS / VSC / TRAC"
4) Choose "Reset Memory"
5) Reset Memory is COMPLETE!
Once the process has been completed run a scan on the ABS system to confirm no fault codes are present to ensure the procedure was completed properly.
If you don't have a scan tool then Toyota has a manual procedure for doing Zero Point Calibration:
1. Turn the ignition key on (engine off), and jump terminals Ts and CG on the DLC3 connector four times within eight seconds. The VSC light will come on indicating its memory has been cleared.
2. Turn off the ignition. Turn the key back on again. The VSC light should come on and remain on for about 15 seconds, then go off.
3. Wait two seconds, and turn the key off. Connect terminals Ts and CG again, then turn the key back on. The VSC light should come on and start to blink after about four seconds. Wait two more seconds, then turn the key off.
4. Now drive the vehicle for about five minutes so the VSC module can relearn the steering sensor zero point. That should do it.