Operation CHARM: Car repair manuals for everyone.

Initial Inspection and Diagnostic Overview

TROUBLESHOOTING
- If the system is functioning correctly, the lamp check should occur and then all lamps / LED's should turn off.
- If the lamp test does not occur
^ Check connectors and fuse/harnessing - open short circuits.
^ Check DTC's.
^ If diagnostics cannot be entered, replace the receiver with a known good one (follow configuration & learning procedure).

TREAD WARNINGS
- Information to ascertain (TREAD Lamp)
^ Was puncture repair fluid used (it should not be)?
This can cause the sensor pressure port to block and incorrect warning to occur.
^ What temperature were tires last inflated at?
At what temperature did warnings occur?
Pressure change is approx. 1.5 psi / 10 degrees C increase.
^ Have the tires been checked / inflated since the lamp first came on?

- If the TREAD Lamp is on:
^ Check for short circuits.
^ Enter Diagnostics and read TREAD Warnings Local Identifier Data.
^ Check to see if warning type is under inflation or leak.
^ If the warning is for under inflation, then:
a. Re-inflate the wheel with the matching sensor ID to it's desired Placard pressure.
b. Check to make sure that the TREAD lamp turns off (this may take up to 1 minutes if the tire is not rapidly re-inflated).
^
a. If the warning is for a leak, then:
b. Fix any puncture and re-inflate the tire to the desired Placard pressure.
Wait up to 1 minutes and make sure that the TREAD lamp turns off and the lamp does not turn on again.
c. If lamp comes on again:
d. Re-check pressure for signs of a puncture and Re-Check TREAD Warnings Local Identifier Data.

- If the Placard pressure is OK and the TREAD lamp still does not turn off:
^ Turn wheel a quarter turn and again wait 1 minutes (the sensor may be in an RIF null).
^ If the lamp still does not turn off:
check for loose receiver wiring and replace the receiver with a known good one if necessary (follow configuration & learning procedure).
- If the problem still exists, replace sensor.
- Ensure that all tires are inflated to their correct Placard pressures.
- Clear TREAD warnings.
- Test drive the vehicle and ensure that the TREAD lamp does not come back on.

DTC'S
- Information to ascertain (DTC Lamp)
^ At what temperature did the DTC occur? Under certain conditions (approx.-40 degrees C/F), a RIF channel missing / hardware failure DTC may occur. This is due to the battery behavior.
- DTC's should be retrieved by using Hi-Scan diagnostic tool.
- The fault should then be diagnosed and rectified.
- DTC's should then be cleared.