Actron 9640 user manual GM Enhanced OBD II Diagnostics, Readiness, Trans Hist P1800, Xfer B2725

GM Enhanced (OBD II) Diagnostics

GM ENHANCED (OBD II) DIAGNOSTICS

IMPORTANT

This system applies to GM vehicles manufactured from 1996 to present. Some GM vehicles in 1994 and 1995 were equipped with

this system. Refer to “Appendix A - Data Link Connectors". GM

vehicles manufactured from 2002 to present automatically use Global OBD II Diagnostics.

✓If an Error Message displays, make sure the OBD II connector is securely attached, and the ignition key is ON. Cycle the ignition key to OFF for 10 seconds, then ON. This may be required to reset the computer. If required, select YES to try again. If the problem still exists, refer to “Error Messages” on page 9-2.

✓Specific GM Enhanced functions are defined in this section. Refer to “Section 4 - Global OBDII Diagnostics" for other functions.

Manual Info

The Manual Info function, instructs the user what section of the manual to use. This section covers GM Enhanced (OBD II) Diagnostics.

I/M Readiness 5

Refer to “” on page 4-1 of Global OBDII Diagnostics.

Read Codes

The Read Codes function retrieves Diagnostic Trouble Codes (DTCs) from the vehicle’s computer module(s). This function can be performed with the KOEO or KOER. These codes cause the computer to illuminate the Malfunction Indicator Lamp (MIL) when an emission-related or driveability fault occurs. The MIL is also known as the “service engine soon” or “check engine” lamp.

The GM Enhanced reads DTC’s from the engine or powertrain module (ENG), Transmission Module (Trans), or Transfer Case Module (XFER).

TRANS Hist P1800		XFER B2725
TCM Power		Active Trnsfr Case
Control	Relay	Mode Switch Malf
Circuit	Open
Transmission Module		Transfer Case Module

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