OBD-II
The ECM monitors system operation using inputs from various sensors and stores Diagnostic Trouble Codes (DTCs) to aid in fault diagnosis. System requires either one or two drive cycles before a DTC is stored. With the exception of catalyst efficiency, all inputs and outputs will have been checked by the end of an appropriate drive cycle. The catalyst monitoring test requires 3 drive cycles, which include a period of steady driving.
FREEZE-FRAME DATA
Freeze-frame data provides a snapshot of conditions present when an emission-related DTC is stored. Once one set of freeze-frame data is stored, this data will remain in memory, even if another emission-related DTC is stored, with the exception of misfire or fuel system DTCs. Once freeze-frame data for a misfire or fuel system DTC is stored, it will overwrite any previous freeze-frame data, and will not be further overwritten.
MALFUNCTION INDICATOR LIGHT (MIL)
For most DTCs, the MIL will illuminate when a fault is detected on the second drive cycle. Only catalyst-damaging misfires, certain internal ECM failures and Controller Area Network (CAN) faults will illuminate the MIL when the fault is detected on the first drive cycle. In certain circumstances, the Message Center, located near speedometer, will display fault warning information simultaneously with the MIL, or when a fault is detected on the first drive cycle.
DRIVE CYCLE
The drive cycle confirms the presence of a fault and the repair of a fault. After a repair is completed, appropriate drive cycle must be performed to confirm repair. There are 4 different drive cycles, defined by the DTC, that can be performed to confirm the repair. For most DTCs, it is not necessary to drive the vehicle to complete a drive cycle. See PERFORMING DRIVE CYCLE under SELF-DIAGNOSTIC SYSTEM.
PERFORMING DRIVE CYCLE
Note. If performing drive cycle for multiple DTCs, which fall into more than one drive cycle, perform drive cycle that requires engine running or vehicle being driven first.
Drive Cycle No. 1
After performing repairs for DTCs listed, turn ignition on and wait specified amount of time to ensure DTC is cleared. See DRIVE CYCLE NO. 1 table.
| DTC | Ignition On Time |
|---|---|
| P0102, P0103, P0106, P0107, P0112, P0113, P0117, P0118, P0121, P0122, P0123, P0222, P0223, P0327, P0328, P0332, P0333, P0405, P0406, P0460, P0568, P0603, P1104, P1121, P1122, P1123, P1221, P1222, P1223, P1226, P1227, P1228, P1229, P1230, P1236, P1237, P1238, P1240, P1241, P1242, P1243, P1392, P1393, P1397, P1398, P1611, P1612, P1637, P1638, P1642, P1643 | 5 Seconds |
| P0560 | More Than 32 Seconds |
| P0566 | 70 Seconds |
| P0567 | 70 Seconds |
| P0569 | 10 Minutes |
| P0570 | 10 Minutes |
| P1224 | 160 Seconds |
| P1260 | 6 Seconds |
| P1609 | 7 Seconds |
DRIVE CYCLE NO. 1
Drive Cycle No. 2
After performing repairs for DTCs listed, start engine and let it run under conditions specified to ensure DTC is cleared. See DRIVE CYCLE NO. 2 table.
| DTC | Time | Coolant Temperature - °F (°C) | Engine Speed | Other Conditions |
|---|---|---|---|---|
| P0111 | 30 Seconds | Less Than 104 (40) | Idle | (1) |
| P0131, P0151, P0171, P0172, P0174, P0175 | More Than One Minute | More Than 176 (80) | 1300-4500 RPM | Engine RPM Steady |
| P0132 | More Than 4 Seconds | (1) | (1) | (1) |
| P0135 | More Than 30 Seconds | (1) | (1) | (1) |
| P0137, P0138, P0157, P0158 | More Than 17 Minutes | More Than 158 (70) | (1) | Ambient Air Temperature Less Than 158°F (70°C) |
| P0152 | More Than 4 Seconds | (1) | (1) | (1) |
| P0155 | More Than 30 Seconds | (1) | (1) | (1) |
| P0201-P0208 | More Than 30 Seconds | More Than 176 (80) | 400-2500 RPM | After Start |
| P0300-P0308 | (1) | (1) | 500-2500 | Engine RPM Steady |
| P0335 | More Than 5 Seconds | (1) | Cranking | (1) |
| P0340 | More Than 5 Seconds | (1) | (1) | (1) |
| P0351-P0358 | More Than 5 Seconds | (1) | Less Than 3000 RPM | (1) |
| P0441 | More Than 10 Minutes | More Than 176 (80) | (1) | Idle For 20 Seconds |
| P0444, P0445 | More Than 10 Seconds | (1) | Idle | (1) |
| P0506, P0507 | More Than 100 Seconds | More Than 158 (70) | (1) | Transmission Oil Temperature 104-212°F (40-100°C) |
| P1235 | More Than 15 Seconds | Ambient Temperature | (1) | (1) |
| P1245 | (1) | (1) | Cranking | (1) |
| P1250 | More Than 3 Seconds | More Than 176 (80) | 1000-3000 RPM | (1) |
| P1313, P1314 | 30 Seconds | (1) | Idle | (1) |
| P1316 | 2 Minutes | (1) | Idle | (1) |
| P1336 | More Than 5 Seconds | (1) | (1) | (1) |
| P1367, P1368 | More Than 5 Seconds | (1) | Less Than 3000 RPM | (1) |
| P1475, P1476 | 5 Seconds | (1) | (1) | Allow Fans To Cycle |
| P1517 | (1) | (1) | (1) | Engine Crank, But No Start |
| (1) Condition does not apply to this DTC. | ||||
| (1) | Condition does not apply to this DTC. |
DRIVE CYCLE NO. 2
Drive Cycle No. 4
After performing repairs for DTCs listed, drive vehicle under conditions specified to ensure DTC is cleared. See DRIVE CYCLE NO. 4 table.
| DTC | Speed MPH | Time | Coolant Temperature - °F (°C) | Engine Speed | Other Conditions |
|---|---|---|---|---|---|
| P0101 | 43-59 | More Than 10 Seconds | More Than 158 (70) | 1500-2500 RPM | Throttle Position 7-200 Degrees |
| P0116 | More Than 12 | 2 Minutes | Ambient Temperature | More Than 1500 RPM | Ambient Temperature More Than 176°F (80°C) |
| P0133, P0153 | 50-62 | More Than 10 Seconds | More Than 158 (70) | 1500-2500 RPM | Airflow 10-40 Grams/Second |
| P0140, P0160 | 12 | More Than 22 Minutes | More Than 122 (50) | More Than 1500 RPM | (1) |
| P0400 | 50-59 | 6 Seconds | More Than 176°F (80°C) | 1700-2050 RPM | (2) (3) |
| P0420, P0430 | 50-59 | More Than 15 Seconds | More Than 104 (40) | 1500-2300 | (2) (4) |
| P1246 | 0-12-0 | (1) | (1) | Idle-1200 RPM-Idle | (5) |
| P1252 | (1) | 30 Seconds | (1) | (1) | Cruise Control Engaged |
| P1396 | More Than 12 | More Than 2 Seconds | More Than 176°F (80°C) | More Than 1700 RPM | (1) |
| P1475, P1476 | (1) | (1) | More Than 176°F (80°C) | (1) | Cooling Fans Cycle On & Off |
| P1516 | 50-62 | More Than 30 Seconds | More Than 176°F (80°C) | 1800-2200 RPM | (1) |
| P1571 | (1) | More Than 15 Seconds | (1) | (1) | Cruise Control Engaged |
| (1) Condition does not apply to this DTC. (2) Perform this cycle after 3 minutes of normal, varied driving. (3) During cycle, release and immediately depress accelerator pedal. (4) With intake air temperature at 68°F (20°C) and throttle constant. When completed, decelerate to 31-37 MPH (with engine speed at 1100-1900 RPM). Keep throttle constant at this speed for more than 55 seconds, then turn ignition off. Repeat 3 times. (5) Accelerate to 12 MPH, then stop. Repeat 5 times. | |||||
| (1) | Condition does not apply to this DTC. |
| (2) | Perform this cycle after 3 minutes of normal, varied driving. |
| (3) | During cycle, release and immediately depress accelerator pedal. |
| (4) | With intake air temperature at 68°F (20°C) and throttle constant. When completed, decelerate to 31-37 MPH (with engine speed at 1100-1900 RPM). Keep throttle constant at this speed for more than 55 seconds, then turn ignition off. Repeat 3 times. |
| (5) | Accelerate to 12 MPH, then stop. Repeat 5 times. |
DRIVE CYCLE NO. 4
SUMMARY
If no hard trouble codes (or only pass codes) are present, driveability symptoms exist or intermittent Diagnostic Trouble Codes (DTCs) exist, proceed to TROUBLE SHOOTING - NO CODES article for diagnosis by symptom (i.e., ROUGH IDLE, NO START, etc.) or intermittent diagnostic procedure.