OBD, GENERAL INFORMATION
The following table provides quick links to information.
| Generic Scan Tool Information Contents. Refer to GENERIC SCAN TOOL INFORMATION CONTENTS . | |
|---|---|
| OBD Systems. Refer to OBD SYSTEMS . | |
| Malfunction Indicator Lamp Illumination. Refer to MALFUNCTION INDICATOR LAMP ILLUMINATION . | |
| CAN Data Link. Refer to CAN DATA LINK . | |
| Electronic Power Control Warning Lamp. Refer to ELECTRONIC POWER CONTROL WARNING LAMP . |
DIAGNOSTIC MODES DESCRIPTION
The information provided in Modes 01 through 09 displays the various levels of emission related data that may be monitored, as well as the ability to retrieve and read stored DTC trouble codes, generate readiness codes, and select the various PIDs and Test-IDs used within the modes to monitor the engine, and emission related component parameters.
The following table provides a link to all diagnostic modes that monitor all components and systems which influence the emission quality.
Note. Depending on scan tool and protocol used, the information in diagnostic mode 01 may be referred to by different names such as Test-ID (TID), Hex-ID, Component-ID (CID), or On-Board Diagnostic Monitor Identifier (OBDMID).
READINESS CODE DESCRIPTION
Diagnostics are performed at regular intervals during normal vehicle operation. After repairing an emissions related system, a readiness code is generated by road testing the vehicle.
If a malfunction is recognized during the drive cycle, it will be stored in the DTC memory.
The OBD drive cycle operation will be monitored with a hand held diagnostic tool. Consult the manufacturer's instruction information for correct tool operation.
The readiness code is erased every time the DTC memory is erased or any time the battery is disconnected. If the DTC memory has been erased or the battery is disconnected, a new readiness code must be generated.
Only erase the DTC memory if a DTC has been stored.
General Recommendations
Most monitors will complete easier and quicker using a "steady-foot" and "smooth" acceleration during the drive cycle operation, cruise, and acceleration modes.
Operating Conditions
For the EVAP monitor test, the coolant temperature and the ambient air temperature must be between 10° C and 35° C with a difference between them no greater than 4° C. The ambient air temperature must not change more than 4° C during the drive cycle procedure (e.g. when driving out of a heated workshop in the winter).
Test requirements
- Erase the DTC memory.
- Coolant temperature must be between 80°C and 110°C.
- The Intake Air Temperature (IAT) must be between 10°C and 35°C.
- Battery voltage must be a minimum of 12.5 volts.
- Fuel tank level 1/4 to 3/4 full.
| WARNING | When performing the drive cycle operation, pay strict attention to driving conditions and please observe and obey all posted speed limits. Failure to follow these instructions may result in personal injury or possible death. |
Drive Cycle Procedure
Connect the scan tool.
Switch the ignition on and start the vehicle.
Idle the vehicle for 2-3 minutes. This executes the O2S Heater, Misfire, Secondary AIR, Fuel Trim, and Purge system monitors.
Drive the vehicle at 45-55 mph for a continuous 7- minute period, avoid stopping. This executes the EVAP, O2S, Fuel Trim, and Misfire monitors.
Accelerate the vehicle to an engine speed of 5000 RPM (with automatic transmission use the tip-tronic mode); lift off the throttle until the engine speed is around 1200 rpm. This executes the fuel cut off
Accelerate the vehicle smoothly to 60-65 mph, cruise constantly for 5 min, this executes the Catalyst; O2S, Misfire, Fuel Trim, and Purge System monitors.
Decelerate and idle the vehicle again for 3 minutes. This executes the Misfire, Secondary AIR, Fuel Trim, and Purge system monitors.
Check the status of the readiness code.
Note. Depending on the scan tool used. The readiness code status may be displayed as complete, passed or OK.
If any engine monitor fails the drive cycle test. Repeat the drive cycle test until all engine monitors have successfully run through and passed.
Note. When repeating the drive cycle operation for a failed EVAP monitor or thermostat-monitor, allow the engine to cool until the coolant temperature and the ambient air temperature are be between 10°C and 35°C with a difference between them no greater than 4°C is observed and repeat the drive cycle operation.
If the drive cycle operation fails again.
Check the DTC memory for stored DTC's.
Repair the vehicle if necessary.
Repeat the drive cycle operation until all engine monitors have successfully run through and passed.
Remove the scan tool and switch the ignition off.
End of operation.