Electrical-Body a Chassis

ELECTRICAL-BODY A CHASSIS

CONTENTS OF THIS SECTION Page Lighting System...... 12- 1 Instruments and Gauges...... 12-12 Horns, Directional Signal, and Windshield Wiper and Washer...... 12-15 Trouble and Remedies...... 12-25 Wiring Diagrams...... 12-28

LIGHTING SYSTEM

INDEX Page Page Maintenance and Adjustments...... 12- 1 Headlamp Panel Motor...... 12- 8 Headlamp Panel Travel Adjustment...... 12- 1 Removal...... 12- 8 Stop Light Switch Adjustment...... 12- 2 Installation...... 12- 9 Headlamp Adjustment (T-3 Aimer Method). . 12- 2 Lighting Switch Replacement...... 12- 9 T-3 Aimer Calibration...... 12- 4 Stop Light Switch Replacement...... 12-10 Headlamp Adjustment Dimmer Switch Replacement...... 12-10 (Aiming Screen Method)...... 12- 5 Parking Brake Alarm Switch Replacement. .. 12-10 Service Operations...... 12- 7 Parking Lamp Service...... 12-10 Sealed Beam Unit Replacement...... 12- 7 Tail, Stop and Directional Signal Lamp Service 12-10 Headlamp Panel Replacement...... 12- 7 License Plate Lamp Service...... 12-11

MAINTENANCE AND ADJUSTMENTS

HEADLAMP PANEL TRAVEL ADJUSTMENT The headlamp panel travel is limited by two adjust- ing screws which are located on the arms of the shaft mounted stop (fig. 1). 1. Raise hood and as a safety precaution install a bolt through the hole in the hood support-secure bolt with a nut. 2. Adjusting screw (A) Figure 1 limits headlamp panel travel in open position-adjust this screw so that mounting face of panel is within 2 degrees of vertical in the fully open position. NOTE: Each headlamp operates independently of the other, therefore individual adiustment is required for each panel. I J 3. Adjusting screw (B) Figure I limits headlamp panel travel in closed position-adjust this screw Fig. 1-Haadlamp Panal Tmvel Adju%tingScrews ELECTRICAL-BODY AND CHASSIS 12-2

so that panel is flush to upper body panel in the reaches the end of free movement. fully closed position. 3. Check pedal position in the fully released position; 4. Lock both screws by tightening lock nut against make sure that pedal rests firmly against rubber stop. stop and that stop light is off. 5. Remove safety bolt as installed in Step 1 and 4. Tighten locknuts to 7-10 ft. lbs. and again check close the hood. operation of stop light switch.

STOP LIGHT SWITCH ADJUSTMENT HEADLAMP ADJUSTMENT 1. Stop light switch actuation is controlled by the (T-3 HEADLAMPSI brake pedal movement; therefore, make sure brake CAUTION: Before attempting to align head- pedal free movement is in accordance with limits lamps, make sure headlamp panel is ad- as outlined in Section 5. justed properly-refer to "Headlamp Panel 2. Loosen the two locknuts (fig. 2) and move stop Travel Adjustment." light switch forward or backward as required, so that electrical contact is made when brake pedal When aiming headlamps, vehicle should be filled to capacity with gas, oil, and water but no load. Tires should be uniformly inflated to recommended pressure. The T-3 Safety Aimer-Type B (fig. 3), is used for the headlamp aiming description that follows. 1. Drive vehicle onto selected aiming area. Tires should be at recommended pressures, and the vehicle should be unloaded-no extreme load in trunk and no passengers.

CONNECTORS

Fig. 2-Sloplighl Switch Inslallation Fig. 3-T-3 Safely Aimer-Type B

Fig. 4-Aimerr and String inslolled on Hoadlamp Unilr ITypicall

CORVETTE SHOP MANUAL ELECTRICAL-BODY AND CHASSIS 12-3

2. Remove headlamp bezel. 3. Mount the T-3 Aimers on either the No. 1 or No. 2 pair of headlamps so that the points of the head- lamps engage the smooth inner ring of the aimers. 4. Secure the aimers to the headlamp units by pressing knob extending out from center of aimer base firmly. Rotate the crossarms to approximately horizontal position and pointing toward center of the car. NOTE: Moisten suction cups slightly to obtain maximum holding force. 5. With both aimers in place on the same pair of headlamp units, knot both ends of the elastic string and fasten, using slots provided, from the left to the right aimer across the top of the hori- zontal crossarms (fig. 4). 6. Rock the car gently to equalize the springs. 7. Rotate both aimers so that the points of the cross- arms just clear the string. Fig. 6-Heodlomp Vertical Adiurtment

HORIZONTAL ADJUSTMENT window of each aimer. If not, loosen knob beneath aimer arm and slide back and forth 8. a. Turn, horizontal aiming screw, fig. 5, on left- until the numeral does appear. hand lamp until the string is positioned over b. Turn headlamp vertical aim screw, fig. 6, on the crossarm centerline. Turn the screw clock- the left-hand unit counterclockwise until the wise in making the final adjustment to take up bubble is at the end of the level toward the play in the headlamp mechanism. T-3 unit. Then turn screw clockwise until the b. Repeat the same operation on the right-hand bubble is centered. lamp to complete the horizontal adjustment of the pair of lamps. c. Repeat this operation on the right-hand head- lamp unit. VERTICAL ADJUSTMENT 10. Recheck the string at the ends of each crossarm for correct setting and the bubble on each aimer 9. a. Numeral "2" should appear in the DOWN for centered position. 11. Remove the aimers by pulling on the suction cup tabs through the openings in the aimers (fig. 7)

Fig. 5-Headlamp Horizontd Ad/ugfmenl Fig. 7-Removing Aimer From H~mdl~mp ELECTRICAL-BODY AND CHASSIS 12-4

MEASUREMENTS FOR LOCATING SCREWS

Fig. 9-Checking Varticai Calibration

VERTICAL CHECK OF AIMER lox10 " \ 1. With the numeral "2" in the DOWN window of the aimer, hold the aimer seating plane against the three screws on the plywood board with the Fig. 8-74 Airnar Checking Fixtura horizontal arm parallel to the floor, Figure 9. If the bubble is centered, the aimer is in calibration. and mount the aimers on the other pair of head- lamp units. Repeat steps 4 through 10. 2. If the aimer is not centered, adjust screw, Figure 12. When both pairs of headlamps have been properly 12, on the bottom of the aimer until the aimer is aimed, remove the safety Aimers and replace the centered. The aimer is now calibrated vertically. headlamp bezel. T-3 AIMER CALIBRATION HORIZONTAL CHECK OF AIMER The factory calibration of the T-3 Aimers may be 1. Rotate the airner so that the horizontal arm points quickly checked by using an easily constructed check- toward the floor (fig. 10). Tie a small weight on ing fixture (fig. 8). Construct such a Mureas follows: the end of a three foot string and connect the op- posite end of the string to the slot in the aimer 1. Fasten a 10 inch square of 3h" plywood to the arm. The string should fall as shown in Figure wall. 10. If it falls outside the tolerance shown, the 2. Install three %" No. 6 pan head wood screws on aimer should be replaced. the wooden board as shown in Figure 8 so that the screw heads are approximately Y4 inch from the board. 3. Set the numeral "2" in the DOWN view window of the aimer. 4. Hold the seating plane of the aimer in contact with the three screws and with the horizontal arm parallel with the floor, Figure 9. The screw heads must be long enough to provide clearance between the flange of the aimer and the board. 5. Adjust the three woodscrews until the bubble in the T-3 Aimer is centered. Leave the wood screws in this position. After the checking fixture has been constructed and ' adjusted as outlined above, the T-3 Aimers may be quickly and easily checked should they ever be dropped or damaged. Fig. 10-Checking Horizontal Cmlibralion ELECTRICAL-BODY AND CHASSIS 12-5

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VERTICAL AIMING SCREW VIEW WINDOWS

L J Fig. 1 1-Salecling Level Aiming Area

HOW TO SELECT A LEVEL AIMING AREA 1. Select area you believe to be level. 2. Remove headlamp bezels and install Aiiers on each headlamp (fig. 4) making sure aiming lugs engage smooth inner ring of the Aimer. To install Aiier, press firmly on the knob extending out from the center of the Aimer base. This forces the suction cup into place on the Sealed Beam unit. Fig. I?-Turning Level Adlusting Srmw la Calibmlo Alrnar 3. Loosen the slider knob beneath the aimer arm and set the numeral "2" in the DOWN view win- TO COMPENSATE FOR UNLEVEL FLOORS dow (fig. 11). Back vex-tical lamp adjuster out on If your floor is not level within the limits specified, each lamp until bubble is outside of black line of the T-3 Aimer can be calibrated to compensate for the vial, then center bubble in between black line of error in the floor. Follow this procedure with both vial by turning clockwise. aimers. 4. After both bubbles are centered, turn the car 1. Drive the car onto the area for which you wish to around end for end, making sure the tires rest in compensate the aimers, and install the aimers in the spots made on the floor before the car was moved. place on the headlamps. 5. If the bubbles are still within the two outside 2. Loosen knob beneath the aimer arm and move the black marks on the vials, the floor is level enough slider until the bubble is centered. to use the Aimer as it comes from the factory. 3. Record the numeral in the view window. (This numeral is to be used only for recalibration.) NOTE: A quick level check can be made by 4. Move the slider to a position halfway between this using the T-3 Safety-Aimer as a level. Use with recorded numeral and the numeral "2" in the a true eight to ten foot two by four as an ex- DOWN window. (This numeral is used only in tension. Make sure pads on base of Aimer are recalibration and not for headlamp aiming.) used. Place the board where you expect the wheels to be and take readings as outlined 5. Recalibrate aimers by turning screw shown in above. Figure 12 until the bubble is centered. 6. The T-3 Aimers are now calibrated for the se- 6. If either bubble moves outside the black lines of lected area. All future aiming must be done in the the vial there is too much slant to the floor. Try same area and with the car pointed in the same driving the car in at different angles onto the aim- direction. Mark the tie spots on the floor so that ing area. If bubbles can not be centered follow future cars can be located in the same position. procedure under "To Compensate for Unlevel Floor." HEADLAMP ADJUSTMENT (AIMING SCREEN METHOD) NOTE: When level portion of floor is obtained, mark tire spots on floor so spots can be used Information relative to aiming the headlamps with- next time without calibrating Aimer. out using the T-3 Aimer is contained in Figure 13.

SORVEnE SHOP MINUAL ELECTRICAL-BODY AND CHASSIS 12-6

UNIT NO. 2 UNIT NO. 1 UNIT NO. 1 4d UNIT NO. 2 f< u LJ

X I CAR GROUND LlNE VIEW LOOKING INTO FRONT OF CAR HORIZONTAL 5 OF SEALED BEAM UNlT I AND HORIZONTAL LlNE I HEADLAMP TO SCREEN DISTANCE- 25' I I - t X

GRWND LlNE L VlEW OF SCREEN LOOKING FROM DRIVERS SEAT OF CAR

UPPER BEAM ADJUSTMENT

UNIT NO. 2 I UNIT NO. 1

I GROUND LINE VlEW LOOKING INTO FRONT OF CAR t HORIZONTAL 5 OF SEAL BEAM UNlT I HEADLAMP I TO SCREEN TOP OF BEAM DISTANCE- 1"- PATTERN 25' - 1 " t '. lr \ t 4,. X I ! ' GROUND LlNE 1 I VIEW OF SCREEN LOOKING FROM DRIVERS SEAT OF CAR

WHENLOWERBEAM ADJUSTMENT IS COMPLETED ON NO. 2 UNITS THE UPPER BEAMS IN THESE UNITS ARE CORRECTLY MADE AUTOMATICALLY. LOWER BEAM ADJUSTMENT

THE ABOVE ARE THE RECOMMENDED SETTINGS. FOLLOW STATE OR LOCAL RECOMMENDATIONS WHEN IN CONFLICT WITH ABOVE

Fig. 13-Headlamp Aiming Guide ELECTRICAL-BODY AND CHASSIS 12-7

SERVICE OPERATIONS

SEALED BEAM UNIT REPLACEMENT nosed pliers to engage retaining spring in hole in retaining ring. Refer to Figure 14 for Headlamp details. 6. Check operation of unit and replace headlamp 1. Position the headlamp panel in the open position; bezel, being sure to index tabs at top of bezel remove two headlamp bezel retaining screws, dis- before installing bottom retaining screws. engage bezel from tabs at top of panel and remove bezel. HEADLAMP PANEL REPLACEMENT 2. Using a pair of long nosed pliers, disengage the spring from the retainer ring and remove two Refer to Figure 14 for Panel Mounting details. retainer ring attaching screws. Do not disturb the 1. Remove engine compartment hood as outlined in adjusting screws. Section 1. 3. Remove the retainer ring, disconnect sealed beam 2. Actuate headlamp panel to the open position. unit at connector and remove unit. NOTE: In the event headlamp motor is in- 4. Attach connmtor to new sealed beam unit, position operative, manual positioning of the panel unit in sub body, being sure that the number molded into the lens face is at the top. can be accomplished by turning the knurled knob at inboard end of motor. As an assist NOTE: In the Chevrolet dual headlamp in- in manual operation of panel, apply light hand stallation the inboard unit (No. 11 takes a pressure to panel in desired direction of double connector, the outboard unit (No. 21 rotation. takes a triple connector plug. 3. Remove positive lead from battery terminal. 5. Position retaining ring into place and install the 4. Remove headlamp bezel retaining screws and lift retaining ring attaching screws, then use long bezel from aligning tabs at top of panel.

Fig. 14-Haadlamp, Headlamp Panel and Motor Dabilr

CORVETTE BHDP MANUAL ELECTRICAL-BODY AND CHASSIS 12-8

5. Remove the sealed beam housing unit as an as- against bearing, being sure that index mark on sembly-disconnect sealed beam leads at harness stop is aligned with flat on pivot shaft. Install connector and remove connector from sealed beam stop lock bolt and torque bolt to 45-60 in. lbs. Make leads; remove the housing-to-panel retaining sure that side-to-side panel alignment is not screws and remove housing unit and wiring from changed when installing and tightening the stop. panel. CAUTION: Do not exceed specified torque when 6. Remove motor from panel pivot shaft-see motor tightening stop lock bolt. removal procedure. Then remove the panel stop from panel inboard pivot shaft, and disconnect 15. Check and align panel to body as follows: switch lead wires from panel, support-mounted a. Tighten panel pivot support bolts snugly but motor switch. still allowing panel to be moved by applying 7. Remove the panel retaining bolt access hole plugs hand pressure. from inside the panel then rotate panel as re- b. Position panel to the closed fposition and align quired and remove the retaining bolts and slide with body so that all surfaces are flush. supports from ends of panel pivot shaft. Remove bearing, felt seal, retainer and washer from in- c. With the panel in the closed position the out- board pivot shaft. board access hole is aligned with the forward bolt head. Tighten this bolt with the panel in 8. Remove panel from its location by alternately the closed position-access to bolt head can be disengaging pivots from their retaining slots and obtained by working through opening between withdrawing unit forward through opening in the hood and body. body (fig. 15). d. Rotate panel to obtain access to each bolt head 9. Loosen allen screw in spacer and disassembly parts and torque bolts to 100-140 in. lbs. from the panel outboard pivot shaft. e. Connect switch lead wires to support-mounted 10. Install washer, retainer, felt seal, bearing and limit switch. spacer, in that order, to panel outboard pivot shaft. 16. Install sealed beam housing unit and at the same Do not tighten spacer on shaft at this time. time position sealed beam lead wires through panel 11. Position panel in body opening and index panel outboard pivot shaft. Install housing unit retaining pivot shafts in retaining slots; then loosely install screws and install lead wires in connector, making support retaining bolts. sure to match colors between harness and 12. Install washer, retainer, felt seal, bearing and connector. support, in that order, to panel inboard pivot shaft, 17. Install motor assembly-see motor replacement and loosely install support retaining bolts. procedure. 13. Check side-to-side alignment of panel, making 18. Connect positive lead to battery terminal. sure that there is no panel-to-body contact; 19. Adjust headlamp panel a$ outlined under "Head- position spacer snugly against bearing; then lamp Panel Travel Adjustment." tighten spacer seat screw to 30-50 in. lbs. 20. Adjust headlamp aiming as outlined under 14. Install stop on panel inboard shaft so that it rests "Headlamp Adjustment." 21. Install headlamp bezel and engine compartment hood-refer to Section 1 for hood installation.

HEADLAMP PANEL MOTOR Refer to Figure 16. REMOVAL 1. Raise hood and as a safety precaution install a bolt through the hole in the hood support-secure bolt with a nut. 2. Remove positive lead from battery terminal. 3. Disconnect motor lead wire and position it out of the way. 4. Turn the knurled knob at inboard end of motor until the gear seems to turn freely-turn the knob in one direction until a definite drag is experi- enced then rotate knob approximately six complete turns in the opposite direction.

CORYmE SHOP MANUAL ELECTRICAL-BODY AND CHASSIS 12-9

Fig. 16-Headlamp Panel Acluating Mofor Mounting

NOTE: The above step is necessary to produce the switch shaft retainer (fig. 17) and remove a no-load condition on the drive gear and to knob and shaft assembly. permit separation of motor from the panel 4. Remove the retaining ferrule nut using Tool J- pivot shaft. 7673. Remove the bezel and switch assembly from 5. Remove the retainer from groove in motor locating instrument panel. stud then remove the motor-to-support retaining 5. Disconnect the multi-plug connector from the screw and remove motor assembly from the lighting switch. A screwdriver may be inserted in vehicle. the side of the switch to pry the connector from the switch. INSTALLATION 6. Connect the multi-plug connector to the new light switch. Connect positive lead to battery terminal 1. Rotate motor and headlamp panel as required to and check operation of light switch in all positions. align slot in motor with headlamp panel pivot shaft, and install motor on shaft so that the bracket 7. Position switch in panel mounting hole and install is aligned with the locating stud. bezel (lettering up) and ferrule nut. NOTE: It may be necessary to turn knurled- 8. Insert switch control knob and shaft assembly knob on end of motor to permit alignment of into switch until retainer engages shaft. of motor with shaft. 2. Slide motor onto shaft until it seats against shaft shoulder; then install retainer in groove on locating stud. 3. Install motor-to-support retaining screw making sure ground wire is installed between screw head and bracket. 4. Connect motor lead wires, making sure that con- tacts are clean and that connection is secure. 5. Connect positive lead battery terminal, remove bolt from hood support, close hood and check operation of headlamp panel.

LIGHTING SWITCH REPLACEMENT Refer to Figure 17. 1. Disconnect positive lead at battery. 2. Pull control knob out to headlamp ON position. 3. Reach under the instrument panel and depress Fig. 174nslrurnsnl Panel Controls

CORVETTE EHDP MANUAL