T e c h 4 0 0 S D E
User Guide R.59
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APPENDIX D: TPMS SYSTEM REVIEW
When diagnosing TPMS systems, understanding what the
tell-tale light means is important.
When cycling the ignition for off to run, the TPMS tell-tale
should come on, and go off. This would indicate a system
with no fault present.
If the light comes on, and stays on for an extended period of time, this would
be a pressure problem. Check the tyre pressures, and adjust to placard. NOTE:
Some vehicles are equipped with sensors in the spare. Also, with some vehicles,
over pressure may turn on the light.
If the light comes on, and continues to flash, there is a system problem. System
problems can range from faulty sensor(s) to sensors on
the vehicle that haven’t
been learned to that vehicle.
Solid Light: Pressure Problem
Flashing Light: System Problem
APPENDIX E: MODES and MODE CHANGING
The TECH400SDE tool has the ability to perform the necessary mode changes
required for TPMS sensors to take them from the shelf, and fit them to the
vehicle. In some cases, these will happen automatically when activating the
sensors.
Some sensors are supplied in a sleep mode that will not allow the sensor to
perform as the vehicle needs them to in a drive condition. This is done to
preserve battery life for the sensors while sitting on the shelf.