Monitors, Trips, Drive Cycles and Readiness Codes
Readiness Code
=> [ Readiness Code, Reading ]
=> [ Readiness Code, Generating ]
The readiness code is an 8 digit number block that indicates the results of an emission relevant On Board Diagnostic (OBD).
When the diagnostic for a system (e.g.: secondary air system) has run through successfully, the respective digit of the number block is set from 1 to 0.
Diagnostics are performed at regular intervals during normal vehicle operation. After repairing an emissions-related system, the readiness code should be generated via a road test to ensure that these systems are working according to specifications. If a malfunction is recognized during the diagnostic, it is stored in DTC memory.
The readiness code is erased every time the DTC memory is erased and every time the voltage supply is interrupted. For this reason, only erase DTC memory if there is a DTC stored in it.
Readiness Code, Reading
Requirements
• There must not be any DTCs stored in DTC memory => [ Diagnostic Mode 03 - Read DTC Memory ] Diagnostic Modes 01 - 09, Diagnostic mode 3: Check DTC memory.
Work Procedure
- Connect diagnostic tester.
- Start engine and let run at idle.
- Under address word 33, select "Diagnostic mode 1: Check measured values".
- Select desired measuring value "PID 01".
- Observe right 8-digit number block: If all diagnostics have run through successfully, the following specified value 8-digit number block must appear: 00000000.
Evaluation PID 01 - System Status-Information, Right 8-Digit Number Block
If a 1 is displayed instead of a 0 in the 8-digit number block:
- Generate readiness code => [ Readiness Code, Generating ].
Readiness Code, Generating
Requirements
• Fuses in fuse box (instrument panel, left) must be OK:
• Battery voltage (both batteries) must be at least 11.5 Volts.
• All electrical consumers such as, lights and rear window defroster must be switched off.
• For vehicles with automatic transmission, selector lever must be in "P".
• If vehicle is equipped with an air conditioning system, this must be switched off.
• The Ground (GND) connections between engine, transmission and body must be OK.
• There must not be any DTCs stored in DTC memory => [ Diagnostic Mode 03 - Read DTC Memory ] Diagnostic Modes 01 - 09, Diagnostic mode 3: Check DTC memory.
• Intake air temperature 5 to 35°C => [ Diagnostic Mode 01 - Read Current System Data ] Diagnostic Modes 01 - 09, Diagnostic mode 1: Check measured values; PID 15: Intake air temperature
• Fuses in right instrument panel fuse holder must be OK:
Right instrument panel fuse holder
Work Procedure
- Connect diagnostic tester.
- Perform test drive. The following operating condition must be met during this road test:
• Coolant temperature must reach at least 80°C => [ Diagnostic Mode 01 - Read Current System Data ] Diagnostic Modes 01 - 09, Diagnostic mode 1: Check measured values; PID 05, Coolant temperature.
Observe safety precautions that apply to road tests. Refer to Repair Information.
Let vehicle cool off with the ignition switched off until the following condition is met:
• Coolant temperature approx. intake air temperature (5 to 30°C) => [ Diagnostic Mode 01 - Read Current System Data ] Diagnostic Modes 01 - 09, Diagnostic mode 1: Check measured values; PID 05, Coolant temperature.
- Perform a road test again. The following operating conditions must be met during this road test:
- Accelerate vehicle uniformly, not at Wide Open Throttle (WOT).
- Drive for 10 minutes in the highest gear or in the highest driving mode on a level driving surface at a constant speed in the range of 65 to 80 km/h at an engine speed of 2000 to 2500 RPM.
• Vehicle speed => [ Diagnostic Mode 01 - Read Current System Data ] Diagnostic Modes 01 - 09, Diagnostic mode 1: Check measured values; PID 13, Vehicle speed.
• Engine speed => [ Diagnostic Mode 01 - Read Current System Data ] Diagnostic Modes 01 - 09, Diagnostic mode 1: Check measured values; PID 12, Engine rotations per minute (RPM).
- After 10 minutes, downshift until an engine speed of 2800 to 3500 RPM has been reached.
- Drive in deceleration mode at a speed up to approx. 1800 RPM.
- Park vehicle and let engine run at idle for 3 minutes.
• Accelerator pedal must not be operated during this time.
- Perform a road test again. The following operating conditions must be met during this road test:
- Accelerate vehicle uniformly, not at Wide Open Throttle (WOT).
- Drive for 10 minutes in the highest gear or in the highest driving mode on a level driving surface at a constant speed in the range of 65 to 80 km/h at an engine speed of 2000 to 2500 RPM.
- Park vehicle and let engine run at idle for 3 minutes.
• Accelerator pedal must not be operated during this time.
- Read readiness code => [ Readiness Code, Reading ].
If a 1 is displayed instead of a 0 in the 8-digit number block:
- Perform a road test again. The following operating conditions must be met during this road test:
- Drive for 10 minutes in the highest gear or in the highest driving mode on a level driving surface at a constant speed in the range of 65 to 80 km/h at an engine speed of 2000 to 2500 RPM.
- Park vehicle and let run at idle for 3 minutes.
• Accelerator pedal must not be operated during this time.
- Read readiness code => [ Readiness Code, Reading ].
In 8-digit number block:
• Display position 5: Secondary air injection (AIR) system
and/or
• Display position 6: Evaporative emissions (EVAP) system
a 1 instead of 0 is displayed:
- Repeat work procedure completely.