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[1] B18 (Altitude Pressure Sensor) Signal: Short Circuit to Positive / Open Circuit In Wiring



[1] B18 (Altitude Pressure Sensor) Signal: Short Circuit to Positive / Open Circuit In Wiring [P0108]

Check component B18 (Altitude pressure sensor)

Test 1: Check actual value B18 (Altitude pressure sensor)
Test 2: Test voltage supply of component B18 (Altitude pressure sensor)

1 Check actual value B18 (Altitude pressure sensor)

Test sequence
- Switch on ignition.
Status of relevant actual value:
- Atmospheric pressure: Communication with ECU required

Specified value
- Atmospheric pressure [950 ... 1100] hPa

Note: The atmospheric pressure is 950 to 1100 mbar (the pressure may be lower in high mountainous regions). (1mbar = 1hPa)

Question: Is the actual value o.k.?

2 Test voltage supply of component B18 (Altitude pressure sensor)

Test prerequisite
- The actual value is not o.k





Test sequence
- Switch off ignition.
- Detach the socket at the component B18 (Altitude pressure sensor).
- (B18) 3<-->1 (B18)
- Switch on ignition

Specified value
- Voltage [4.8 ... 5.2] V

Question: Is the measured value okay?

No
- The measured value is not o.k.
Possible cause and remedy
- Cable for voltage supply
- N3/10 (ME-SFI control module)
**End of test**

Yes
- The measured value is o.k.
Possible cause and remedy
- Signal wire
- B18 (Altitude pressure sensor)
**End of test**