Headlamp - Aiming Procedure Update

91pontiac05

Bulletin Number: 91-8-12
Reference Number: 138201R
Publish Date: 4/91


Subject:
SERVICE MANUAL UPDATE - SECTION 8B LIGHTING AND HORN (NEW HEADLAMP AIMING PROCEDURE)

Models Affected:
1988-91 LEMANS MODELS


This bulletin cancels and supersedes the "Lighting Adjustment" procedure found under On-Vehicle Service in Lighting and Horns, (Section 8B), of the 1988 through 1991 Pontiac LeMans Service Manual. The procedure in the manual refers to a J 25300-203 aiming adapter -- this tool is incorrect. The correct tool is a J 25300-202 aiming adapter. Both are included in the J 25300-B headlamp aimer kit. Refer to this bulletin whenever aiming of LeMans headlamps is necessary.

Headlamp Aiming

The J 25300-B headlamp aimer kit includes adapters to fit all vehicles manufactured in the United States, as well as many foreign models. Always aim headlamps in pairs. Refer to the following guidelines and to the headlamp aimer manufacturer's instructions when adjusting headlamp aim.

FIGURE 1:

FIGURE 2:

COMPOSITE HEADLAMP

Composite Headlamp Aiming

Figures 1 and 2

Tools Required:

J 25300-B Headlamp Aimer

J 25300-202 Composite Headlamp Aimer Adapter (Larger Pad Pattern)

1. Aiming should take place with the vehicle parked on a flat surface. If no flat surface is available, follow the manufacturer's instructions to adjust the aimer for "Floor Slope Calibration."


2. Rock vehicle to equalize the shocks and springs.

3. Clean headlamp lenses and aiming pads. Thoroughly clean all cleaning solution from lenses and attaching pads as some cleaners will weaken the attaching pad.

4. Check for burned bulbs, proper beam switching and broken aiming pads.

5. Attach a J 25300-202 composite headlamp aimer adapter to each J 25300-B headlamp aimer.

FIGURE 2:

6. Adjust the three adjustment rods of the J 25300-202 adapter to the specifications imprinted next to their corresponding adjustment pads on the headlamp lens. These numbers are designed to compensate for the degree of inclination from vertical of the headlamp lens. Proper setting of the aimer adapter adjustment rods to the headlamp lens adjustment pads will place the J 25300-B aimer on a completely horizontal axis, which is absolutely necessary for proper headlamp aiming (Figure 2).

FIGURE 1:

HEADLAMP AIMING

7. Be sure to install the right and left aimers on the correct sides.

8. Adjust headlamp aim according to the manufacturer's instructions. Set horizontal adjustment first, using the horizontal adjustment screws located near the inside upper corner of the headlamp lens. Then set the vertical adjustment, using the vertical adjustment screws located on the backside of the composite headlamp (Figure 1).