FixVault

Hazard warning lights switch (25): Connection

The lead to the button is supplied 10.2 V via a BCM integrated resistor of 1.5 kO. Control module inputs are digital; voltage over 2V is interpreted as an open circuit while voltage lower than 2V is interpreted as closed.

Fig 1: Identifying Communication Flow - Hazard warning lights switch
G03717838Courtesy of SAAB-SCANIA OF AMERICA, INC.
Fig 2: Hazard warning lights switch - Circuit Diagram
G03717839Courtesy of SAAB-SCANIA OF AMERICA, INC.

The indicator lamp in the button is supplied battery voltage from BCM in order to light.

Switch mounted in ACC (216): 

CONNECTOR PINOUTS REFERENCE

Pin No. Signal type Description
15 Ground ACC control module's ground connection in the body
19 Supply from BCM Supply to indicator lamp from BCM pin A17 (K78)
26 Supply from BCM From BCM pin B61 (K78), the pin is grounded when it is pressed in

Switch mounted in MCC (504): 

CONNECTOR PINOUTS REFERENCE

Pin No. Signal type Description
2 Supply from BCM Supply to indicator lamp from BCM pin A17 (K78)
10 Ground MCC control module's ground connection in the body
19 Supply from BCM From BCM pin B61 (K78), the pin is grounded when it is pressed in