XC70 AWD L6-3.2L VIN 98 B6324S (2009)
The function of the main relay (system relay) is to supply certain components with voltage.
The relay is mechanical and has a closing and opening function. In the rest position the circuit in the relay is open.
The main relay terminals (#30 and #86) are supplied with voltage by the battery. When the starter button on the start control module (SCU) has been
activated and the engine control module (ECM) is powered, the terminal (#85) on the main relay is grounded by the engine control module (ECM).
When the terminal (#85) is grounded, the relay is activated and a number of components are powered via the relay terminal (#87).
The main relay is in the integrated relay/fuse box in the engine compartment and is diagnosed by the engine control module (ECM).
Injectors
The function of the injectors is to spray fuel into the cylinders in the correct spray patterns. This happens sequentially.
The injectors are located along the intake pipe.
The engine control module (ECM) controls the injectors by grounding the valves in pulses.
The injectors can be diagnosed by the engine control module (ECM) and can be activated.
Ignition coils
The ignition coils supply the spark plugs with high voltage to produce sparks. The engine control module (ECM) controls the ignition coils so that sparks
are generated at the correct time. The signal reconnects to the engine control module (ECM) so that diagnostics can be carried out.
Each ignition coil has an integrated power stage.
The ignition coils are in the sparkplug wells above each spark plug.
The control module checks the ignition coils' function using one separate diagnostic lead.
Camshaft reset valve (CVVT)
