72-22Fault code 18 · Lumbar pressure sensor - open circuit

911 Turbo (996) Seat memory S02; S03; 72 72-22Fault code 18 Lumbar pressure sensor - open circuit Diagnostic conditions • Ignition on • Switch for memory seat adjustment actuated Possible cause of fault ♦Short circuit to ground/open circuit in pressure sensor supply lead ♦Pressure sensor faulty ♦Control module faulty Affected terminals Plug 9, pins 1, 2 and 3 Diagnosis/troubleshooting Work instruction Display OK If not OK 1 Visual inspection ♦Check plug 9 on control mod- Step 2 Connect plug 9 or ule for corrosion and contact. repair wiring har- ness. ♦Check supply lead on plug 9 → End for damage. 2 Check power supply of ♦Switch off ignition. Approx. 5 V Step 5 the sensor Step 3 ♦Pull off plug on lumbar adjust- ment device (pressure sensor). ♦Measure voltage between pin 1 and ground. 3 Check ground lead of the ♦Measure voltage on plug of Approx. 5 V Step 7 sensor lumbar adjustment device Step 4 (pressure sensor), between pins 1 and 3. 4 Check signal lead of the ♦Select 'Pressure sensor volt- 0 V without jumper Step 8 sensor age' in the Actual values menu and approx. 5 V item. with jumper. Step 10 ♦Connect jumper between pins 1 and 2. 7298 Fault code 18 72-22 page 1 Printed in Germany – 42, 2003 18xxxs02