Shift Indicator Light - Revised Description

85saab01

FILE IN S.I. Man VOL. I

SEC. 3 PG. 83
Service Information

SUBJECT: SHIFT INDICATOR LIGHT ISSUE: 03/85-748 M85-1/2, 8 VALVE w/MANUAL TRANSMISSION



During mid-M85 production a Shift Indicator Light system was introduced. This system has a light in the dashboard cluster which indicates ideal shift points for optimized fuel economy and minimal vehicle wear.



Beginning with VIN Serial Nos.:
System Description:

The system is controlled by rpm signals from the ignition coil and vacuum from the intake manifold through a vacuum switch. When engine rpm is above approx. 1800 rpm and the vacuum in the intake manifold is 0.3 bar or greater the indicator light in the dash will light.

To ensure that the correct shift points are indicated to the driver, the following components also provide specific signals to the system.

Gear Indicator Switch - Deactivates system when 5th gear is engaged (located on gearbox cover at 5th gear).


Temperature Switch - System functions only when engine temperature is above approx. 95~F (35~C). (Threaded into intake manifold flange between cylinders 2-3).


Throttle Switch - De-activates system when throttle is closed. (Incorporated into existing black throttle switch housing.)


System Relay - Contains all system relay circuits and also delays the activation of the upshift light by 1.7 seconds and by 1.5 seconds the time it takes before going out. The time delay function prevents irritating blinking of the light in high torque situations.



Component Location and Part Numbers:




Wiring Diagram: