Readiness Code, Function

Readiness Code Readout
The readiness code indicates whether all of the prescribed diagnosis could be carried out by the system.

The readiness code can be read with scan tool VAG 1551 and 1552 using address word "01" or with address word "33" in mode "1".

The creation and reading of the readiness code is described in "Checking and Generating Readiness Code". Monitors, Trips, Drive Cycles and Readiness Codes

Procedure:

Creation of the Readiness Code
The readiness code can be created in two ways:

1. The FTP72-Driving-Cycle was completed

or

2. The diagnosis was deliberately performed by service personnel.

The creation of the readiness code through Driving-Cycle happens automatically through daily use of the vehicle by the driver.

To save time and not require service personnel to perform the Driving-Cycle possibly several times during troubleshooting, the possibility was created to perform the diagnosis in the workshop stall. However, the diagnosis requirements listed in the repair manual must be strictly adhered to.

Summary of Readiness Code/Workshop Diagnosis

The readiness code does not give any information, whether any malfunctions are actually present in the system. For the driver or road side inspection personnel, the only optical indication, that one or more malfunctions were detected and stored, is the illuminated

MIL.

The readiness code indicates only, that the specific diagnosis were completed (bit at 0), not yet completed or has been interrupted (bit at 1).

Once the engine management system has detected a malfunction and it has met the storage prerequisite, the DTC can be stored in the DTC memory. Thereafter the DTC can only be read with a generic scan tool or the VAG scan tool.

Only at this point can the location of the DTC be determined. For instance, the secondary air injection or the exhaust gas recirculation.

After the malfunction has been repaired, the technician erases the DTC. This also resets the readiness code. The readiness code will also be reset, when the ECM is disconnected (e.g. transport onboard a ship or disconnecting the battery). This means (depending on vehicle type) that the ECM must perform all diagnosis again.

For this reason, the DTC memory should not be erased unnecessarily, and the technician should avoid disconnecting the ECM unnecessarily.