900 SE Sedan L4-1985cc 2.0L DOHC Turbo EFI (1996)
5
Be sure to check whether the "CHECK ENGINE" lamp (MIL) or any other warning lamp is on.
6
Faults may be persistent or intermittent.
A persistent fault continuously meets the fault criteria, i.e. the fault exists only under certain conditions. Examples of such conditions are:
-
Faulty connectors (see point 4).
-
Electromagnetic interference. Interference may consist of electromagnetic radiation emanating from the car's own equipment or from powerful
broadcasting transmitters when the car is driven past radio and TV masts, high-tension transmission lines and places like airports, etc.
-
Faulty components. Switching functions in relays, solenoids, etc. may cause interference through arcing as the contacts make and break.
Intermittent faults require careful analysis to ensure that components in perfect working order are not changed unnecessarily.
7
In general:
-
When connecting a BOB, make sure that the ignition switch is in the OFF position.
-
When unplugging connectors, make sure that the ignition switch is in the OFF position.
-
When taking resistance readings, make sure that the ignition switch is in the OFF position.
8
Measuring the resistance of solenoids and relays.
The nominal resistance is specified at 20°C (68°F). The resistance of the winding is strongly temperature-dependent and increases with rising
temperature.
Exercise caution when judging the results of such resistance measurement.
