Exterior Mirror - Inoperative
Group: 66Number: 00-04
Date: Oct. 30, 2000
Subject:
Exterior Rear-view Mirror, Function Change
Model(s):
All except Cabriolet, TT 1999
Supersedes T.B. Group 66 Number 99-02 date Mar. 17, 1999
Condition
Heated exterior rear-view mirror element appears to be inoperative.
Production
As a running change beginning January 1999 a thermo-switch has been added to the heated mirror glass.
With the ignition key switched ON, the thermo-switch allows current flow to the mirror heating element when outside ambient temperatures are less than 59°F (15°C) +/- 10°F (3°C) and stops current flow when outside ambient temperatures are above 77°F (25°C) +/- 10°F (3°C).
Service
If you suspect a heating element of a exterior rear-view mirror is inoperative, the following procedure can be used to check element:
- Remove mirror glass (see appropriate Repair Manual for removal procedure).
Mirrors with thermo-switch can be identified by thermo-switch -1- on the reverse side of glass.
- Connect an ohm meter to the terminals of the mirror -arrow-.
- Using special tool US 1122 (hot / cold sensor tester) or equivalent, to lower temperature of thermo-switch below 59°F (15°C).
^ Thermo-switch should close and ohmmeter should show approx 3-6 ohms
- Now apply warm air using special tool US 1122 (hot / cold sensor tester) or equivalent, to raise temperature to above 77°F (25°C)
- 10°F (3°C) while observing ohmmeter.
^ Thermo-switch should open and ohmmeter should show (infinity)
- Replace mirror if necessary.
Note:
When ordering a mirror, only mirrors with thermo-switch are available.
New version mirror (with thermo-switch) can be retrofitted on vehicles from 1997 --> 1999.
When installing a new version mirror, it is only necessary to replace the inoperative mirror, DO NOT replace mirrors in pairs.