Checking the Brake Lights Switch (Not TCS)

In order for the Cruise Control system to work, at least one of the brake light bulbs must be OK.

This means that pin G (7) of the Cruise Control connector must be grounded (through the brake light bulbs) before the Cruise Control system can be activated.

1 Check that the brake light bulbs are OK.
If they are not, change them.
2 If the brake lights do not work, continue fault diagnosis as described in the "Brake lights" section of Service Manual 3:2 "Electrical system, system diagrams, operation and fault-tracing". If the brake lights work, check the operation of the Cruise Control system.
3 If the Cruise Control system still does not work, check that about 12 V is present across pin G (7) of the Cruise Control connector and a good ground when the brake pedal is depressed.
If the voltage is OK, continue fault diagnosis as described "Before Control Module Replacement".






4 If the voltage is not OK, check the wiring for continuity or a short circuit by measuring the resistance across pin 1 of the brake lights switch and pin G (7) of the Cruise Control.
If the resistance is > 1 ohm, rectify the fault.
If the resistance is ≤ 1 ohm, continue fault diagnosis as described in "Lighing and Horns/Brake lights" system diagrams, operation and fault-tracing".