Quote:
Originally Posted by kipps
The horn is on the wiper/washer switch plug. So the wires are in close proximity at the steering column.
The horn relay, hazard flasher, and door/ignition buzzer are on the "convenience center" in GM's terms. Basically a small steel bracket that holds all three items and a pile of wires. Look for that unit somewhere down low in the dash area, and check for current at the horn relay. Then trace it back up to the wiper switch plug. If no problems between the relay and the switch, suspect the wiper switch.
|
NO! The horn trigger wire is separate from the wiper wiring til it enters the cab harness.
Backfeeding from bad grounds causes all kinds of odd operational issues. Til the grounds are known to be good you will have a devil of a time finding any other issues. You could have damaged wiring or switches but the ground(s) need to be good to troubleshoot them.
The horn trigger from the button is in the Harmonica plug on the column along with the turnsignals/key-inserted/brake-lamp wires.
The wipers are either off the dash switch (pre 83ish) or, on 84 & later cabs with column wiper switches, plugged on the bottom third of the column. The wiper/washer plug position in the picture below may be on the base or side of the column tube on some models instead of on top but it's near where this drawing shows it.
From the 1991 Upfitters guide... should also be on PDF page 388 of the 1991 wiring diagrams. Applies to 84-91 CK/RV squares but the 1990 & 1990 RV wiring diagrams and upfitter guides are the only place to find wiring plug locations drawn in this manner. Thankfully GM didn't change a lot of these kind of routing and switch locations so it makes it easier to track down locations on the earlier models as well... they did change some but this is a good jumping off point.
C210 is the Headlamp Dimmer
C241 is the Wiper/Washer
C207 is the Ignition Switch
C212 is the Turn-Signal Harmonica plug (Turn/Hazard/Brake/Horn/Key-Inserted)
S206 is the driver side dash harness.
