P1603 Fault Code

Jaguar – TRANSMISSION CONTROL MODULE (TCM) – EEPROM MALFUNCTION

For Jaguar, P1603 is logged when the transmission control module (TCM) has detected an issue with the electrically erasable programmable read-only memory (EEPROM)

EEPROM is used to store small datasets in the control module during operation. This means this issue is strictly related to the coding of the control module.

It most commonly is logged when there is an issue with the vehicle’s battery. This is extended to when replacing the battery. Even once the new battery has been installed, this code can be logged. This happens even though there is no problem at hand.

This fault code often does not warrant any concern as it can simply be cleared, which solves the issue.

See generic codes: There is no similar fault code for this issue.

Audi – INTERNAL CONTROL

For both Audi and Volkswagen, P1603 is logged when an internal issue is detected with the powertrain control module (PCM).

The various control modules in a vehicle are onboard computers that take in information from various inputs from components around the vehicle, process the data, and then use it to optimize a number of important functions.

This code indicates that the control module has an internal issue, causing it to malfunction.

This can cause a host of issues with the operation of the vehicle as the ECM controls a huge array of functions within.

It is important with any control module issues to have them resolved immediately to restore the driveability of the vehicle.

See generic codes: P0607

BMW – CONTROL MODULE SELF-TEST, TORQUE MONITORING

For BMW, P1603 is logged when the engine control unit (ECU) has detected an issue when undertaking a self-test of the control module.

The ECU will continuously monitor itself for proper operation. This is done due to the importance of the control module for the correct operation of the various systems in the vehicle.

This code is particularly tricky to solve as it does not give a lot of information about the issue. However, any issue with the various control modules can result in plenty of issues throughout the vehicle.

This code has been known to put the vehicle into limp mode, making it very important to have this issue resolved as soon as possible.

Additionally, it can cause the vehicle to stop running completely every time it is logged.

See generic codes:

Chrysler – PCM INTERNAL DUAL-PORT RAM COMMUNICATION FAILURE

For Chrysler, P1603 is logged when the powertrain control module (PCM) has detected an internal issue with itself.

The PCM, like the various control modules in a vehicle, are onboard computers that take in information from various inputs from components around the vehicle, process the data, and then use it to optimize a number of important functions.

This fault code indicates that there is an issue with the dual port of the module in particular. This can be a hardware or software issue.

It is always a good idea to have any control module issues resolved immediately due to their importance in the vehicle.

See generic codes: P0607

Volkswagen – INTERNAL CONTROL MODULE SELF CHECK

For both Audi and Volkswagen, fault code P1603 represents the same issue. For more information on the problem and similar generic fault codes, please see the above description for Audi.

See generic codes: P0607