IONIZATION DETECTION MODULE - CONNECTION DESCRIPTION

Pin No.	Signal type	Description
1	Ignition trigger cylinder 4, in	Synchronization of ionization current measurement for cylinder 4
2	Ignition trigger cylinder 3, in	Synchronization of ionization current measurement for cylinder 3
3	Knock signal, out	Knock signal, raw value to ECM
4	Combustion signal 1, out	Combustion signal, raw value to ECM
5	n/c
6	n/c
7	Ionization signal 2, in	Ionization signal from ignition coil cylinder 2
8	Ionization signal 3, in	Ionization signal from ignition coil cylinder 3
9	Ignition trigger cylinder 1, in	Synchronization of ionization current measurement for cylinder 1
10	Ignition trigger cylinder 2, in	Synchronization of ionization current measurement for cylinder 2
11	Combustion signal 2, out	Combustion signal, raw value to ECM
12	B+	Power supply B+ from main relay
13	B-	power supply B- from grounding point G7
14	n/c
15	Ionization signal 4, in	Ionization signal from ignition coil cylinder 4
16	Ionization signal 1, in	Ionization signal from ignition coil cylinder 1

Fig 1: Identifying Communication Flow - Ionization Detection Module (1 Of 3)

Courtesy of SAAB-SCANIA OF AMERICA, INC.

When to See a Mechanic

Stop DIY work and contact a certified mechanic immediately if any of the following apply:

• You smell fuel, burning insulation, or see smoke.

• Brakes feel soft, pull hard to one side, or make grinding noises.

• The engine overheats, stalls repeatedly, or misfires under load.

• You are missing required tools, torque specs, or safe lifting equipment.

• You are not confident in the next step or safety outcome.

Safety Warning

Ionization Detection Module (740): Connection: Notes