Notes On Trouble Codes
- When certain malfunctions or trouble codes initially occur, they will be temporarily stored in ECM memory, but MIL on instrument panel will not come on.
- The second time malfunction or trouble code is detected, MIL on instrument panel will then come on, provided ignition is turned off and then back on after malfunction or trouble code was first detected. This is referred to as the Two Trip Detection Logic and only applies to specified trouble codes. See TWO TRIP DETECTION LOGIC TROUBLE CODES table.
- In Normal Mode, MIL on instrument panel will go off after malfunction is repaired, but trouble codes, except ECM non-memory Trouble Codes 16, 43, 51 and 53, will be retained in ECM memory until cleared. ECM non-memory trouble codes are not stored in ECM memory.
- In Test Mode, all trouble codes except ECM non-memory Trouble Codes 16, 43, 51 and 53 are retained in ECM memory, even with ignition off and repairs made, until cleared.
NOTE:
When road testing vehicle in Test Mode, the Two Trip Detection Logic will not function. In Test Mode, the MIL on instrument panel will come on the first time malfunction or trouble code is detected.
TWO TRIP DETECTION LOGIC TROUBLE CODES
| Application | (1) Trouble Code |
|---|---|
| SC300 | 21, 25, 26, 27, 28, 71 & 78 |
NOTE:
When in Test Mode, if vehicle is not driven at a speed greater than 6 MPH, ECM will set Trouble Codes 42 and 43. For MIL operation in relation to trouble code when in Test Mode, see TROUBLE CODE IDENTIFICATION table under TROUBLE CODE IDENTIFICATION.