Viper RT-10 V10-8.0L VIN E (1997)
Brake Warning Indicator: Description and Operation
OPERATION
The Red Brake warning lamp is located in the instrument panel and is used to indicate the loss of pressure in the brake hydraulic system or that the
parking brake is applied. In addition, the brake warning lamp is turned on as a bulb check by the ignition switch when the ignition switch is placed
in the crank position. Problems with this system will generally be of the type where the warning lamp fails to turn on when it should, or remains on
when it should not. The warning lamp bulb is supplied a 12 volt ignition feed anytime the lock cylinder (key) is in the on position. The bulb is then
illuminated by completing the ground circuit either through the park brake switch, the brake warning lamp switch, or the ignition switch when it is
in the crank position. The brake warning switch is located in the combination valve. The purpose of the switch is to indicate to the driver that there
is a loss of pressure in the hydraulic system of the vehicle's brakes. This loss of hydraulic pressure can be the result of low brake fluid level or a
leak in the brake hydraulic system.
NOTE: If brake fluid level has dropped in master cylinder fluid reservoir, the entire brake hydraulic system must be checked for evidence of a leak.
CIRCUIT OPERATION
The Brake Warning Indicator lamp is used to alert the operator of a problem with the vehicles braking system. The lamp illuminates when the
ignition switch is turned to the START position to perform a self check.
There are two switches used in this system and they are wired in parallel form. A parking brake switch located on the parking brake mechanism
will illuminate the lamp if the normally OPEN switch is CLOSED.
The other switch used is the brake warning lamp switch. This switch is normally OPEN. When the brake system pressure is below a predetermined
level the switch CLOSES and completes a path to ground from the G99 circuit at the message center, through the switch.
Power for the lamp is supplied on circuit G5. This circuit is protected by a 5 amp fuse located in cavity 11 of the fuse block and is HOT in the
START and RUN position only. Power for the fuse is supplied on circuit A21 from the ignition switch.
