P1641 Engine Management System

Fault symptom
Car fails to start.

Condition
Diagnostic trouble code (DTC) P 1641 stored in the engine management system if alarm code is incorrect.







Diagnostic procedure
1 Check the diagnostic trouble code (DTC) in the engine management system
- Connect an Intelligent Saab Tester (ISAT) scan tool.
- Ignition switch in the "ON" position.
- Select "TRIONIC or "MOTRONIC 2.8.1", as appropriate.
- Select "READ FAULT CODES".

Is diagnostic trouble code (DTC) P1641 stored?
[YES] Continue with point 2.
[NO] Continue fault diagnosis of the engine management system as described in "Powertrain Management/Computers and Control Systems". Testing and Inspection







2 Program the VSS alarm code
- Select "THEFT ALARM".
- Select "IMMOBILIZING".
- Program the correct alarm code in the VSS electronic control module.
- Select "TRIONIC" or "MOTRONIC 2.8.1", as appropriate.
- Select "CLEAR FAULT CODES".
- Try to start the car.

Has it started?
[YES] The remedial measure taken was correct.
[NO] The alarm code is incorrect or absent. Continue fault diagnosis of the engine management system as described in "Powertrain Management/Computers and Control Systems". Testing and Inspection







3 Check the alarm code status in VSS
- Select "THEFT ALARM".
- Select "READ VALUES".
- Select "ALARM CODE".

Is the alarm code correct?
[YES] Continue with point 4.
[NO] The alarm code is incorrect or absent. Continue fault diagnosis of the engine management system as described in Service Manual 2:7.

4 Final test
Start the car and check to see if the fault symptom persists.

Does the trouble persist?
[YES] Continue as described in "Before Changing the Electronic Control Module". Before Changing the Electronic Control Module
[NO] The remedial measure taken was correct or the fault is of intermittent nature.