Dakota 4WD V6-3.9L VIN X (1997)
Horn Relay: Testing and Inspection
WARNING: ON VEHICLES EQUIPPED WITH AIRBAGS, REFER TO AIR BAGS AND SEAT BELTS/AIR BAGS BEFORE
ATTEMPTING ANY STEERING WHEEL, STEERING COLUMN, OR INSTRUMENT PANEL COMPONENT DIAGNOSIS OR SERVICE.
FAILURE TO TAKE THE PROPER PRECAUTIONS COULD RESULT IN ACCIDENTAL AIR-BAG DEPLOYMENT AND POSSIBLE
PERSONAL INJURY.
Horn Relay
Relay Test
The horn relay is located in the Power Distribution Center (PDC) in the engine compartment. Refer to the PDC label for horn relay identification and
location.
Remove the horn relay from the PDC as described to perform the following tests:
1. A relay in the de-energized position should have continuity between terminals 87A and 30, and no continuity between terminals 87 and 30. If OK,
go to Step 2. If not OK, replace the faulty relay
2. Resistance between terminals 85 and 86 (electromagnet) should be 75 ± 5 ohms. If OK, go to Step 3. If not OK, replace the faulty relay
3. Connect a battery to terminals 85 and 86. There should now be continuity between terminals 30 and 87, and no continuity between terminals 87A
and 30. If OK, see the Relay Circuit Test. If not OK, replace the faulty relay.
Relay Circuit Test
1. The relay common feed terminal cavity 30. is connected to battery voltage and should be hot at all times. If OK, go to Step 2. If not OK, repair the
open circuit to the PDC fuse as required.
2. The relay normally closed terminal (87A) is connected to terminal 30 in the de-energized position, but is not used for this application. Go to Step
3.
3. The relay normally open terminal (87) is connected to the common feed terminal 30. in the energized position. This terminal supplies battery
voltage to the horn. There should be continuity between the cavity for relay terminal 87 and the horn relay output circuit cavity of the horn wire
harness connector at all times. If OK, go to Step 4. If not OK, repair the open circuit to the horn as required.
4. The coil battery terminal (86) is connected to the electromagnet in the relay It is connected to battery voltage and should be hot at all times. Check
for battery voltage at the cavity for relay terminal 86. If OK, go to Step 5. If not OK, repair the open circuit to the PDC fuse as required.
5. The coil ground terminal (85) is connected to the electromagnet in the relay It is grounded through the horn switch when the horn switch is
depressed. It can also be grounded by the high-line Central Timer Module (CTM) in response to inputs from the Vehicle Theft Security System
(VTSS) or the Remote Keyless Entry (RKE) system. Check for continuity to ground at the cavity for relay terminal 85. There should be continuity
with the horn switch depressed, and no continuity with the horn switch released. If not OK, see the diagnosis for the Lighting and
Horns/Horn/Horn Switch.
