Starting System: Overview Saab 9-3 I

Identifying Starter Motor (Petrol Engine). Scheme 10

STARTER MOTOR TECHNICAL DATA (PETROL ENGINE)

TEST VALUES LOAD CHART

Identifying Starter Motor (4-Cyl Diesel Engine). Scheme 11

STARTER MOTOR TECHNICAL DATA (4-CYL DIESEL ENGINE)

TEST VALUES LOAD CHART

Identifying Special Tool (Tech 2). Scheme 12

See Tech2 instruction manual.

Group: Test equipment

TESTING EQUIPMENT

Identifying 30 05 378 Clamp Ammeter. Scheme 13

Used with ISAT. For measuring large currents, e.g. starter motor current consumption or generator charge current.

Group: Test equipment

30 05 378 CLAMP AMMETER APPLICATION

Identifying 86 11 857 Test Lamp (Red-Green). Scheme 14

Voltage range 8-16V

Group: Test equipment

86 11 857 TEST LAMP, RED-GREEN APPLICATION

Identifying Starter Components. Scheme 15

1. Starter motor (4)
2. Ignition switch (20)
3. TWICE control module (632)
4. Gear selector, automatic (239/77)
5. Starting relay (517)
6. Immobilizer (463)

Identifying Main Components (LHD). Scheme 16

1. Starter motor (4)
2. Ignition switch (20)
3. TWICE control module (632)
4. Gear selector, automatic (239/77)
5. Starting relay (517)
6. Immobilizer (463)

Identifying Main Components (RHD). Scheme 17

1. Starter motor (4)
2. Ignition switch (20)
3. TWICE control module (632)
4. Gear selector, automatic (239/77)
5. Starting relay (517)
6. Immobilizer (463)

Operation

When the correct ignition key is put in the ignition, the transponder sends a code to TWICE, which grounds the starting relay actuating coil.

As the ignition is turned to start position, the starting relay operates and the operating circuit to the solenoid terminal 50 closes. The solenoid engages the pinion with the ring gear on the engine's flywheel and closes a switch so that the starter motor commutator is supplied with power via the slip brushes from terminal 30.

Once the engine is started and the engine speed exceeds the starter motor rpm, the pinion is disengaged from its shaft via a free wheel, preventing the starter motor from overrevving. Releasing the ignition key breaks the starting circuit and also the operating circuit to the solenoid, whereby a spring returns the pinion to its rest position.

Identifying Immobilization Procedure (TWICE). Scheme 18

As standard, the car is fitted with a system which prevents the car from being started without the correct key. There is a transponder in the key with an identification code that is unique for just that transponder. A receiver fitted round the ignition switch receives the transponder's identification code and sends it on to TWICE, which recognizes the car's transponders. In the event of an incorrect transponder being used, TWICE outputs an error message on the bus.

For more information about the TWICE control module. See BRIEF DESCRIPTION OF TWICE

For more information about immobilization, see IMMOBILIZATION.

Fault Diagnosis Strategy For Electronic Systems Flow Chart. Scheme 19

1. The customer's description of the problem constitutes a basis for the fault diagnosis strategy. If necessary, the customer must demonstrate the trouble on the car to avoid misunderstandings.
2. In certain cases, the function may be correct. 2. a. Good product knowledge is required to decide this. 2. b. If the function is correct, this must be explained to the customer.
3. If the function is judged to be faulty, the car should be repaired. Saab's fault diagnosis strategy assumes that the technician is familiar with the customer's description of the problem. So note the customer's complaint and any other observations on the job sheet.
4. The technician obtains a readout of the diagnostic trouble codes from all systems. A malfunction in one system can often be caused by a fault in another system.
5. The car may contain diagnostic trouble codes which are secondary faults or which have been incorrectly generated. 5. a. Compare the customer's complaint with the symptom descriptions for the various diagnostic trouble codes. EPSI has a fast search path for this. 5. b. If the symptom description for a diagnostic trouble code matches the customer's complaint, this diagnostic trouble code is probably caused by the primary fault. Repair as per instructions.
6. If there is no match with diagnostic trouble codes or symptoms, the technician must diagnose the fault himself. 6. a. In EPSI, search under fault diagnosis on the basis of symptoms in the system where the fault has occurred. 6. b. If the symptom description in the current system matches the complaint, the right fault diagnosis description has probably been found. Repair as per instructions.
7. Certain fault symptoms can be remedied by reprogramming the control module. 7.a. Does the customer complaint stem from a known software problem in a programmable control module? 7.b. Reprogram the control module following the instructions in SPS.
8. If there is no match with diagnostic trouble codes or symptoms, the technician must diagnose the fault himself. A final check must be carried out after the repair. Good technical product knowledge is required to solve this type of problem.
9. The car is ready.

See also:
• CRIMP J162, PASSENGER DOOR HARNESS