Ignition System - Ignition Module Selection
TECHNICAL SERVICE BULLETINBulletin Number: 248-2502
Date: November 2004
Market: all
Correct choice of ignition discharge module
Cars affected
All Saab models with engine management system Trionic T5 and T7.
Background
It is extremely important that the different variants of ignition discharge modules available at Saab workshops are used with the correct engine type. The modules must not be used incorrectly in short-term testing as they could destroy components in both engine control module and ignition discharge module. Faults caused by mixing them do not necessarily appear directly, but may appear a lot later.
Table, colour configuration:
Red and blue ignition discharge modules are identical. Black and green ignition discharge modules are identical.
The differences between red/blue (T5) and black/green (T7) are in:
- Ignition coils (different inductance and voltage type)
- Trigger signals (different sensitivity to external interference)
- Knock signal (different degrees of signal amplification)
- Charge and discharge circuits (different technical concepts)
Disclaimer