1998 S10 Ignition Switch Wiring Diagram

This is a list of the Chevy Color code as recognized by most wiring companies. This is by no means absolutely complete as Chevy changed things here and there as well as had different color codes for options such as Power Windows or Air Conditioning. This is meant as a helpful guide to wiring your car with the basics. By using the color code and gauge size you will be able to wire your car without using labeled wires and thereby saving you money since you only have to get certain colors that work for multiple components eg; 16 Pink for ignition circuits. I hope this helps out some of you guys and if youd like to add to this or if you see a glaring mistake I made feel free to add your revision. Good luck
MAIN POWER DISTRIBUTION

10 RED - ALTERNATOR BAT FEED, IGNITION SWITCH BAT, FUSE PANEL BAT
12 PINK - IGNITION FEED FROM IGNITION SWITCH TO FUSE PANEL
12 BROWN - ACCESSORY FEED FROM IGNITION SWITCH TO FUSE PANEL
12 PURPLE - START CIRCUIT FROM IGNITION TO "S" TERMINAL ON STARTER SOLENOID

TURNSIGNAL SWITCH WIRING

16 LIGHT BLUE - LEFT FRONT TURNSIGNAL
16 DARK BLUE - RIGHT FRONT TURN SIGNAL
16 YELLOW- LEFT REAR TURNSIGNAL
16 GREEN - RIGHT REAR TURNSIGNAL
16 WHITE - BRAKE SWITCH OUTPUT INTO TURNSIGNAL SWITCH
16 PURPLE - TURNSIGNAL FLASHER OUTPUT INTO TURNSIGNAL
16 BROWN - HAZARD FLASHER OUTPUT INTO TURNSIGNAL
16 BLACK - HORN RELAY TRIGGER (THIS IS GROUND)

EXTERIOR LAMP WIRING

14 GREEN - BAT FEED FROM HEADLIGHT SWITCH FUSE INTO BAT TERMINAL OF HEADLIGHT SWITCH
14 BLUE - HEADLIGHT SWITCH OUTPUT INTO CENTER PIN OF DIMMER SWITCH
14 TAN - LOW BEAMS
14 LIGHT GREEN - HIGH BEAMS
16 YELLOW - HEADLIGHT SWITCH PARK CIRCUIT OUTPUT INTO PARK FUSE
16 BROWN - PARK FUSE OUTPUT TO TAIL LIGHTS
16 LIGHT GREEN - REVERSE LAMPS

DASH LIGHT WIRING

18 GRAY - INTERIOR ILLUMINATION (USUALLY POWERED OFF OF TAIL LIGHT FUSE)
18 LIGHT BLUE - LEFT TURNSIGNAL INDICATOR SPLICED OFF OF LEFT FRONT T/S WIRE
18 DARK BLUE - RIGHT TURNSIGNAL INDICATOR SPLICED OFF OF RIGHT FRONT T/S WIRE
16 BROWN - GENERATOR LAMP TO "I" TERMINAL ON ALTERNATOR OR VOLTAGE REGULATOR
18 LIGHT GREEN - HI BEAM INDICATOR SPLICED OFF OF HIGH BEAM CIRCUIT AT DIMMER SWITCH

GAUGE WIRING

18 BLUE - OIL PRESSURE
18 GREEN - WATER TEMP
18 WHITE - TACH
18 YELLOW - VEHICLE SPEED SENSOR + TO ELECTRIC SPEEDO
18 PURPLE- VEHICLE SPEED SENSOR - TO GROUND
***FUEL GAUGE HAS CHANGED A LOT AND CAN BE PURPLE, TAN OR PINK
18 PINK - GAUGE POWER (THIS GOES TO THE IGNITION TERMINAL OF ALL GAUGES AND ONE SIDE OF THE GENERATOR LAMP) ***VOLTMETER USES THIS ALSO

IGNITION SYSTEM

14 OR 12 PINK - COIL POWER, IF USING STANDARD POINTS USE THE 14 GAUGE THROUGH A BALLAST RESISTOR. IF USING HEI USE 12 GAUGE AND NO BALLAST RESISTOR
14 YELLOW - BYPASS LEG FROM STARTER I TERMINAL TO COIL + (THIS APPLIES MAX BATTERY VOLTAGE TO COIL DURING CRANKING ONLY)

WIPERS

14 YELLOW - WIPER POWER INPUT (NORMALLY THIS GOES DIRECTLY TO THE WIPER MOTOR)
14 LIGHT BLUE - WIPER SWITCH TO WIPER MOTOR LOW SPEED
14 DARK BLUE - WIPER SWITCH TO WIPER MOTOR HIGH SPEED
14 BLACK - WIPER SWITCH TO WIPER MOTOR WASHER PUMP

HORN

14 GREEN - HORN RELAY OUTPUT TO HORN

HEATER

12 BROWN - HEATER SWITCH POWER TERMINAL
***DEPENDING ON HEATER SETUP AND THE TYPE OF BLOWER RESISTOR THERE ARE DIFFERENT COLORS NORMALLY RED, YELLOW AND ORANGE FOR THE VARIOUS SPEEDS. I LEFT IT OUT BECAUSE THEY CHANGED HERE AND THERE
KEY ON CIRCUITS

16 PINK - IGNITION INPUT TO REVERSE LAMP SWITCH, TURNSIGNAL FLASHER AND NUMEROUS OTHER KEY ON POWERED ITEMS
18 YELLOW - ACCESSORY CIRCUIT TO RADIO

BATTERY POWERED CIRCUITS (CONSTANT 12V)

16 ORANGE - ORANGE IS USED PRIMARILY FOR ITEMS THAT ARE HOT AT ALL TIMES BUT SWITCHED SUCH AS THE BRAKE SWITCH INPUT, HAZARD FLASHER INPUT, COURTESY LIGHT INPUT AS WELL AS THE TRUNK, HOOD AND GLOVEBOX LIGHTS. THESES ITEM CAN WORK WITH THE KEY OFF BUT THEY ARENT ON ALL THE TIME SO THEY USE ORANGE. CIGAR LIGHTER WILL USE THIS COLOR AS WELL.

COURTESY LIGHT WIRING

16 WHITE - GROUND CIRCUIT FOR COURTESY LIGHTS. THIS WIRE IS SPLICED OFF OF THE DOOR JAMB SWITCHES AND SOMETIMES THE HEADLIGHT SWITCH AND GOES TO ONE HALF OF THE COURTESY LIGHT(S). REMEMBER THAT THIS IS TO ONLY BE WIRED LIKE THIS IF YOU HAVE GROUNDING STYLE JAMB SWITCHES. FORD USES THE OPPOSITE ARRANGEMENT AND RUNS GROUND DIRECT TO THE BULBS AND SWITCHES POWER. NORAMALLY YOU CAN TELL THE DIFFERENCE BECAUSE THE GROUNDING STYLE SWITCHES HAVE ONE TERMINAL AND FORD STYLE HAS TWO TERMINALS. CORVETTES USE A DUAL PIN JAMB SWITCH BECAUSE THEY ARE FIBERGLASS AND CANNOT GROUND THROUGH THE SWITCH BODY SO THE HAVE A SECOND TERMINAL TIED TO GROUND.

Last edited: Mar 13, 2009

vtx1800 and 6inarow like this.
Most excellent info, thanks for posting!
This is awesome. I've been searching the 'net for over a week to find this information. Thanks!
Great, thanks for posting. Do you mind if I pass it on to others? good day
I have a 2002 GMC Sierra and im having to rewire the rear lights. wires were cut and Im trying to reconnect them. I've had to replace the sockets. I don't have yellow, red, white or purple. I only have light blue x3, black x3 brown, brown&w greenx2 please help brown, brown&white, green and dark blue. Please help