900 SE Hatchback L4-1985cc 2.0L DOHC Turbo EFI (1997)
Exhaust System Temperature Indicator: Description and Operation
A warning lamp for catalytic converter overheating is fitted on cars for certain markets.
A voltage is applied to the EXH relay which operates when the temperature of the catalytic converter reaches 825 ± 25°C, causing the warning lamp to
be grounded via pin 12 (12p-2) of the main instrument display panel connector.
The lamp will then remain alight until the temperature drops by about 10°C.
When the ignition is switched on, the lamp is tested for about 3 seconds. If the temperature is within normal limits the lamp will go out.
