Step | Action | Yes | No |
|---|---|---|---|
Schematic Reference: Horn Schematics | |||
1 | Did you review Horns Description and Operation? | Go to Step 2 | |
2 | Depress the horn switch. Does either horn operate? | Go to Horns Inoperative - One Horn in 2005 C/K Truck Service Manual | Go to Step 3 |
3 |
Does either horn operate? | Go to Step 4 | Go to Horns Inoperative in 2005 C/K Truck Service Manual |
4 | Connect a test lamp between terminal 86 of the relay block and ground. Does the test lamp illuminate? | Go to Step 6 | Go to Step 5 |
5 | Connect a test lamp between terminal C of the blackout (B/O) service switch and ground. Does the test lamp illuminate? | Go to Step 7 | Go to Step 8 |
6 | Connect a test lamp between terminal 85 of the relay block and ground. Does the test lamp illuminate? | Go to Step 9 | Go to Step 10 |
7 | Repair the open or high resistance in the (OG) circuit 912. Did you complete the repair? | Go to Step 13 | -- |
8 | Connect a test lamp between terminal B of the blackout (B/O) service switch and ground. Does the test lamp illuminate? | Go to Step 11 | Go to Step 12 |
9 | Repair the open or high resistance in the (BK) circuit 150. Did you complete the repair? | Go to Step 13 | -- |
10 | Replace the horn interrupt relay. Did you complete the repair? | Go to Step 13 | -- |
11 | Replace the blackout (B/O) service switch. Refer to Blackout Lamp Switch Replacement in Lighting Systems. Did you complete the replacement? | Go to Step 13 | -- |
12 | Repair the open or high resistance in the (OG) circuit 40. Did you complete the repair? | Go to Step 13 | -- |
13 | Verify the system operation. Do the horns operate properly? | System OK | Go to Step 2 |
