+30 power supply
Symptom: The theft alarm is not working.
+30 power supply |
Fault symptom
The theft alarm is not working.Important | ||
Drop of +30 power supply to control module brings about total loss of functions. |
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Check the +30 power supply by arming/disarming the anti-theft alarm. |
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US/CA start fault diagnosis with step 1 |
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For EU, start fault diagnosis as point 2. |
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Diagnostic procedure
1 Check fuse 23
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Check that fuse 23 is intact and live.
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Connect the test lamp to the fuse and a good grounding point.
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The test lamp should light.
Is the test lamp on?
yes |
Continue with point 2.
no |
Continue fault diagnosis as described in Service Manual 3:2 Electrical system, "+30 power supply".
2 Check the +30 power supply
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Unplug connector H33-3.
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Connect the test lamp to pin 5 of connector H33-3 and a good grounding point.
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The test lamp should light.
Does the lamp light up?
yes |
Continue with point 4.
no |
Continue with point 3.
3 Check the wiring connected to the fuses
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US/CA
Connect the test lamp to fuse 23 and a good grounding point.
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The test lamp should light.
Is the test lamp on?
yes |
Check and repair or replace the wiring between pin 5 of connector H33-3 and fuse 23.
no |
Continue fault diagnosis as described in Service Manual 3:2 Electrical system, "+30 power supply".
- |
EU
Connect the test lamp to fuse 1 and a good grounding point. |
The test lamp should light.
Is the test lamp on?
Yes |
Check and repair or replace the wiring between pin 5 of connector H33-3 and fuse 1.
No |
Continue fault diagnosis as described in Service Manual 3:2 Electrical system, "+30 power supply".
4 Check the wiring connected to the electronic control module
Check the wiring harness for continuity between pin 5 of connector H33-3 and pin 25 of the electronic control module.The resistance should be < 1 ohm.
Is the resistance correct?
Yes |
Continue with point 5.
No |
Repair or replace the wiring harness.
5 Final check
Check the operation and see if the fault symptoms are still present.Is the problem still present?
Yes |
See "Before replacing a control module".
No |
The remedial measures taken were correct or the fault is of intermittent nature.