Viper RT-10 V10-8.0L VIN E (1997)
Heated Glass Element Relay: Testing and Inspection
Rear Window Defogger Relay
Relay Terminals
The rear window defogger relay is located in the fuse/relay block along side of the speaker amplifier in the rear cargo area. While this relay uses a ISO
relay output terminal configuration it differs from a conventional relay since it incorporates the timer for the rear window defogger as well.
Remove the rear window defogger relay from the fuse/relay block to perform the following tests.
1. Using a Voltmeter, test for B+ in the following terminals.
a. Terminal 87 should read within one of battery voltage. If OK, go to Step 2. If not OK, check fuse 3 in the fuse/relay block.
b. Terminal 86 should read within one of battery voltage, with the ignition switch in the RUN position. If OK, go to Step 2. If not OK, check fuse
8 in the fuse block.
2. Using a Voltmeter, test for B- (ground) in the following terminals. Place the positive lead of the voltmeter in terminal 87. Briefly, touch the
voltmeter to a good ground and observe that the voltmeter reads within one volt of battery voltage. Using the negative lead of the voltmeter, test
for B- in the following terminals.
a. Terminal 85 should read within one volt of battery voltage. If OK, go to Step 2. If not OK, repair the Z1 circuit (relay ground) to ground.
b. Terminal 87A should have continuity to ground when the rear window defogger switch is pressed. If OK, go to Step 3. If not OK, refer to
Windows and Glass/Heated Glass Element/Heated Glass Element Switch/Rear Window Defogger Switch Test.
