Transmission and Drivetrain: Service Precautions
Control modules
Connecting and disconnecting control modules
Always switch off the ignition before connecting and disconnecting control modules, connectors and the breakout box.
The ignition must be switched off when taking readings with an ohmmeter.
Temperature
The control modules must not be heated to above 80°C. Remove control modules when stoving for example.
Arc welding
Always disconnect the battery negative lead to prevent a short-circuit.
Position the welding ground as close to the welding site as possible, otherwise different ground potentials may be generated in different components.
When welding close to an electronic module, the unit must be removed to avoid heat damage.
Replacement
Do not replace a control module without checking its wiring and components. Otherwise the new component may be damaged in the same way as the old one.
Supplementary restraint system (SRS)
Warning: The components in the SRS and SIPS systems must be treated very carefully during repair. This is to help prevent:
1. Personal injury when carrying out repairs
2. Damage to or malfunction of the SRS/SIPS systems. Work on the SRS/SIPS system or components related to the SRS/SIPS system must be carried out by an authorized Volvo workshop.
Note: See the relevant section for further information about safety and repair of the SRS system.
The car has pyrotechnical airbags and seat belt tensioners
The car has the letters SRS stamped into the center of the steering wheel and on the dashboard above the glove compartment. This shows that the car is equipped with driver and passenger side airbags.
There are side airbags in both the front seats.
There is a SIPS bag decal on the windshield and seat compartments to indicate that side airbags are installed.
The letters IC are stamped onto the CD panel.
This indicates that an inflatable curtain is installed. The car is equipped with an inflatable curtain as standard but can be delivered with it deactivated.
The car has pyrotechnical airbags and seat belt tensioners.
All SRS components are activated by signals from various electrical sensors.
Cable harness
Take care not to trap, fray, pierce or damage SRS wiring in any way:
- the soundproofing panel
- the glove compartment
- the dashboard
- steering shaft covers
- the ignition switch
- sill trim panels
- all posts
- the roof
- the parcel shelf.
SRS control module
The SRS control module is located between the parking brake and the gear selector lever in the center console. Never install car accessories on or beside the control module.
Sensors
The collision sensors for the SRS/SIPS system (5) are located in the B-posts, C/D-posts and in the SRS control module. These control all the components in the SRS/SIPS system (4 airbags, 2 inflatable curtains, 5 seat belt tensioners). Never install car accessories on or beside the sensors.
Signal communication
The sensor modules for the pyrotechnical components are located in the bodywork. They can be triggered by a blow to, or pressure on, the bodywork. If the acceleration on the sensor is sufficiently high the sensor(s) will transmit a signal to the control module. The control module transmits an activation signal if the signal from the sensors has been sufficiently high or long-lasting.
Work on the SRS steering wheel module
When carrying out repairs to the steering wheel, steering column or steering gear always follow the appropriate repair procedures. Read the relevant sections, The contact reel in the steering shaft is damaged if the steering wheel is turned more than three turns in one direction, Test output Data Link Connector (DLC) in passenger compartment.
Ignition and high voltage components
Switch off the ignition before:
- Connecting and disconnecting the test instruments
- Connecting and disconnecting the connectors
- Taking readings using an ohmmeter.
High voltage
There are dangerous voltages at all points in the ignition system, including the connectors etc.
Warning: The ignition system operates at high power and voltages. Contact with the high tension circuit-the ignition coil, spark plug caps and distributor cap-is dangerous.
Caution: Because of the fire hazard avoid sparking when working on the fuel system, especially when checking the injectors.
Battery, charging
It is important that the battery voltage is normal (approximately 12 V) when testing the car system components. If necessary a battery charger can be connected during the test. Connect the battery charger to the battery terminals. Charge the battery for approximately 10 hours at the recommended current -maximum 6 A.
Example: If the battery is marked 520 A, the recommended charge current is 0.01x520 = 5.2 A.
A higher than recommended charge current may damage the battery.
Note: Boost charging (with a high current or voltage above 16 V) will damage the battery and is prohibited.
Warning: Explosive oxyhydrogen accumulates when the battery charges. Smoking, welding, grinding or other activities involving sparks or naked flames are prohibited in the vicinity of a charging battery. Only charge the battery in a well ventilated area.
Cleanliness
Cleanliness is particularly important when working on the fuel system.
Clean the fuel line connections thoroughly before disconnecting them.
When compression testing
- Disconnect engine speed (RPM) sensor before carrying out a compression test.
- The Diagnostic Trouble Code (DTC) must be erased when the engine speed (RPM) sensor (RPM) has been reconnected.