Electronic Control Module - Software Programming Error

Group
2

Number
9601

Model
6 Cyl

Part Identifier
2470

January 9, 1996

Subject:
Software Programming Error in ECM Affecting Fault Analysis

ATTENTION:
Service Manager / Service Technician

Models Affected:
911 Carrera Model Year 1996
911 Turbo Model Year 1996

General Information:

A programming error in the ECM has resulted in the omission of two areas of mode 2 Freeze Frame (instantaneous operational condition) data:

- Regulation factor for Oxygen sensor regulation, Bank 2 (cyl.4-6).

- Adaption value for the Oxygen sensor regulation, Bank 2 (cyl.4-6).

This information cannot be read out with a scan tool and the values in the control unit memory cannot be retrieved.

The menu text:





O2S.- Integr. B2..... % and
O2S.- Adapt. B2....... %
are not shown by the scan tool (see the OBD II workshop manual page B-21).

This software error is in vehicles produced before the following VIN numbers:

99 1 TS 32 0192 911 Carrera Coupe
99 1 TS 34 0161 911 Carrera Cabrio
99 1 TS 37 5557 911 Turbo

ECM's with corrected software are installed in production as of August 31, 1995.

Parts Information:

The part number for the 911 Carrera ECM remains unchanged:
993 618 604 00 911 Carrera

The part number for the 911 Turbo ECM has changed:
993 618 666 01 911 Turbo

Repair Information:

The missing "Bank 2" values mean only that the information cannot be used for fault analysis. A replacement of the ECM is not necessary.

For fault analysis the corresponding values from "Bank 1" can be used as equivalent information for the missing "Bank 2" values.

However, if a leak in the intake or exhaust system is present (indicated through fault codes P1123...P1130), the leak has to be repaired before using "Bank 1" values as substitutes for "Bank 2" values for diagnosis of possible further problems.

Warranty Information:

Replacement of control unit for this programming error is not a warranty matter.