Vehicle is equipped with self diagnostics. Check if your vehicle is equipped with 12-pin or OBD-II DLC. If any trouble codes are present, it would assist in getting to the source faster.
RETRIEVING CODES (WITHOUT SCAN TOOL)
Following procedure is for vehicles equipped with a 12-pin Data Link Connector (DLC). On vehicles equipped with 16-pin DLC (OBD-II vehicles), DTCs can only be retrieved using scan tool.
1. Turn ignition on. DO NOT start engine. MIL should glow. Locate Data Link Connector (DLC) attached to control module wiring harness. Most DLCs are located under dash on driver's side of vehicle. Turn ignition on with engine not running. Connect jumper wire from terminal "B" (diagnostic test terminal) to terminal "A" (ground) of DLC. See Fig. 1.
Inserting jumper wire into test and ground terminals of DLC with engine running will cause fuel injected vehicles to enter field service mode. MIL will not indicate codes if this is done.
On vehicles equipped with 2.3L engine, Code 12 should always exist when DLC is grounded with Key On and Engine Off (KOEO).
2. MIL should begin to flash codes. Each code will be repeated 3 times. For example, FLASH, FLASH, pause, FLASH, longer pause, identifies Code 21. First series of flashes is first digit of trouble code. Second series of flashes is second digit of trouble code.
3. Trouble codes are displayed starting with lowest numbered code. Codes will continue to repeat as long as DLC test terminal is grounded. If codes are not flashed, or MIL does not glow, self-diagnostics will not work. For diagnosis of this condition, see DIAGNOSTIC CIRCUIT CHECK in BASIC TESTING article in the ENGINE PERFORMANCE section. To exit diagnostic mode, turn ignition off and remove jumper wire from DLC.
Trouble codes will be recorded at various operating times. Some codes require operation of affected sensor or switch for 5 seconds; others may require operation for 5 minutes or longer at normal operating temperature, road speed and load. Therefore, some codes may not set in a service bay operational mode and may require road testing vehicle in order to duplicate condition under which code will set.
Wednesday, December 22nd, 2010 AT 1:53 PM