(TA383-0730) Anti theft alarm activated by glass breakage loop
TECHNICAL ADVICE - Quick information for your help | |
Bulletin Nbr: | TA383-0730 |
Date: ........... | August 2007 |
Market: | All |
Anti theft alarm activated by glass breakage loop |
VEHICLES CONCERNED |
Saab 9-3 (9440) 5-door.
BACKGROUND |
The alarm can falsely be activated because of poor electrical contact in the male and female contact on the three rear windows. The issue can be permanent or intermittent. Caused by cold at night, warm by the sun or vibrations when driving.
CONDITIONS |
Alarm goes off unintended. Customer complaints about:
- False anti theft alarm
- Anti theft display message
SYMPTOM DESCRIPTION |
DTC B0283 Glass break detector, open/short to B+ set.
Anti theft alarm reason is glass breakage loop.
It is possible to have false anti theft alarm of the glass breakage loop without DTC B0283 05 set.
ACTION |
The issue can be in the wiring but it is more likely that it is at the female and male contact at the rear quarter windows (both side and rear windows that has the glass brake loop).
Just by touching the contacts the resistance can disappear so do not touch if wanting to measure the resistance. This could be done in the H102 connector, see WIS for pin-out configuration.
From MY08 resistance can be read out with the Tech2. Normally measured externally max 3 ohm. (OK measured by BCM <500Ohm. NOK measured by BCM >1,5khm).
1. |
Disconnect the female connector from the male contact on the window.
Be careful! The wire can easily be damaged.
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2. |
The male contact consists of two parts. Make sure the “top”
part is not “lose” to the bottom part by moving with finger nails.
Rotate parallel to the window glass.
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3. |
Use electrical contact spray on the male contacts.
Note! Many "electrical contact" sprays has isolating performance together with cleaning. Do not use such spray. The spray used should: remove oxidize, be electrical conductive and prevent against oxide. |
4. |
Connect the female wiring harness contact to the male contact
on the window. Make sure the female is fitted with a firm “snap”
to the male contact. If necessary, “tighten” the female contact.
Repeat item 1 to 4 on all the contacts on all three rear windows. |
Do not mix up the UAM (ultrasonic) sensor with the glass brake loop. If trouble code B0283 is present there is nothing wrong with the UAM.