Interpretation ID: nht88-1.96

TYPE: INTERPRETATION-NHTSA

DATE: APRIL 14, 1988

FROM: C. DIANNE BLACK -- ENGINEERING MANAGER, JAGUAR

TO: ERIKA Z. JONES -- CHIEF COUNSEL, NHTSA

TITLE: FMVSS 108, HEADLAMP LEVELLING SYSTEMS

ATTACHMT: MEMO DATED 8-1-88, TO C. DIANNE BLACK, FROM ERIKA Z. JONES, STD 108

TEXT: Thank you for your letter of February 1, 1988 which discussed our June and October 1987 letters regarding a headlamp levelling system for our US models.

We have reviewed your letter, and we have decided that we should go one step further and provide a drawing of the switch, showing its location on the steering column shroud and to perhaps better describe its operation.

To reiterate from our October 17, 1987 letter, the switch has three positions -

zero = driver only or

driver plus front passenger or

driver plus front and rear passengers

one = driver plus passengers plus maximum trunk load

two = driver plus maximum load in trunk

The switch/lamp motor system is limited to the above three positions and intermediate settings are not possible. The switch is not a rheostat but rather a 'master/slave' unit. The switch is illuminated by turning on the headlamps and it cannot be turne d off.

Headlamp alignment is adjustable only in the zero position.

We believe that full description in the owner handbook, and the fully visible illuminated switch will enhance owner familiarity with the system and the system can be used to enhance headlighting performance.

We hope this will further clarify the system and allay your concerns over our headlamp levelling system and its operation.

Feel free to contact me should you have further questions.

Headlamp Dipped-Beam Levelling Control

Driver's-Eye View (On Left Steering Column Shroud)