Drive Cycles

DRIVE CYCLES

Description

NOTICE: Strict observance of posted speed limits and attention to driving conditions are mandatory when proceeding through the drive cycle.

NOTE: Vehicles equipped with power take-off (PTO) or auxiliary idle control must have that system disengaged before the drive cycle is initiated.

The primary intention of the drive cycle is to clear the DTC P1000 and to satisfy the specifications for the Society of Automotive Engineers (SAE) specification J1979. Each on board diagnostic (OBD) monitor must run during the drive cycle.

If the drive cycle is completed and DTC P1000 is not cleared. Repeat the entire drive cycle. If a particular step is interrupted, simply repeat the drive mode. If the drive cycle is interrupted with a key OFF, only drive modes that were incomplete must be run.

Rough road conditions may prevent certain steady state conditions and steady accelerations from validating the transmission and load-related monitors.

Some monitors may require extended driving.

Drive Cycle Procedure:

NOTE: Make sure a 10 hour cold soak time is allowed before beginning the drive cycle procedure.

1. key ON. Do not crank until the WAIT TO START light cycles, or at least 10 seconds, whichever occurs first.
2. Start the engine. Idle in PARK or NEUTRAL for 40 seconds.
3. Befon3 continuing, the engine oil temperature must exceed 60°C (140°F).
4. The following outlines the appropriate conditions for running certain OBD monitors that require the engine to be under load:
a. Accelerate steadily to third gear (M/T use fourth gear) and hold at 1,500 RPM for 3 seconds. Accelerate steadily from 56 km/h (35 mph) to 105 km/h (65 mph) over approximately 15 seconds (M/T 11 seconds minimum).
b. Repeat Step 4.a. three times while maintaining the conditions in Step 4.a.
c. Before proceeding, turn off all accessories arid disengage tow/haul/overdrive cancel.

5. Idle the vehicle for 2 minutes in PARK or NEUTRAL.
6. key OFF.
7. Start the engine. Idle in PARK or NEUTRAL for 40 seconds.
8. Repeat the Quick Test.

NOTE: If DTC P1000 is present after running the drive cycle:

- Repeat Step 4.a., being certain to maintain a minimum mass fuel desired (MFDES) of 35 mg/stroke above 2,000 RPM for 11 seconds. Also, maintain a minimum MFDES of 30 mg/stroke above 2,800 RPM for at least 6 seconds.
- Repeat Step 8. MFDES must remain below 12 mg/stroke for 11 consecutive seconds.

OBD Parameter Identification (PID) Data Monitor
The PID monitor for OBD offers real time evaluation of several emission-related parameters. The only parameters that apply to diesel applications are diagnostic trouble code count (DTC CNT), manifold absolute pressure (MAP), malfunction indicator lamp (MIL), revolutions per minute (RPM), and vehicle speed sensor (VSS).

Accessing the PID Data Monitor
Refer to the scan tool manufacturer's manual for instructions.

OBD Pending DTCs
Pending diagnostic trouble codes (DTCs) are faults which occurred in the current or the previous drive cycle. They have only set during one drive cycle and may not have set the MIL yet. These DTCs can be identified by using the retrieve pending DTCs feature. Additionally, they are found in the vehicle-specific mode retrieve/clear continuous memory DTCs from the instant the DTC is set.

This function only reports pending concerns that have occurred during the present or previous drive cycle, but does not indicate single concerns that happened on any 2 previous drive cycles.

Accessing the PID Data Monitor
Refer to the scan tool manufacturer's manual for instructions.