For 1990-2009 cars only
- Check condition of circuit breaker #9. If circuit breaker is open, locate and repair cause of overload. Replace circuit breaker if necessary.
- Check that G404 is clean and tight.
- The air brake dryer and moisture ejector heater are both thermostatically controlled. The thermostat will activate the heating element when the valve body reaches a temperature of approximately 7°C (45°F). The heating elements will deactivate when the valve body is warmed to approximately 26°C (85°F).
- If either the air brake dryer or the moisture ejector heater remain engaged above 26°C (85°F), replace the malfunctioning component.
- Check for a broken or partially broken wire inside the insulation which could cause system malfunction but prove good in a continuity/voltage check with the system disconnected. These circuits may be intermittent or resistive when loaded, and if possible, should be checked by monitoring for a voltage drop with the system operational (under load).
- Check for proper installation of aftermarket electronic equipment which may affect the integrity of other systems. Refer to Checking Aftermarket Accessories .
