45-31Fault code 4480 · Booster pump

911 Turbo (996) PSM 05 45 45-31Fault code 4480 Booster pump Diagnostic conditions • Booster pump actual value is evaluated and displays an implausi- ble value Possible cause of fault ♦Short circuit to ground/voltage or open circuit in circuit to con- trol module terminals 2, 3 and 4 ♦Booster pump motor locked up/faulty ♦Wiring/ plug connection faulty Note! Do not jumper the pump; it must not run dry under any circum- stances! Affected terminals Terminals 2, 3 and 4 Diagnosis/troubleshooting Work instruction Display OK If not OK 1 Check supply voltage of ♦Switch off ignition > 11 V Short circuit to the booster pump for ⇒ Step 2 ground or open cir- ♦Pull off the PSM control module short circuit to ground/ cuit between PSM plug open circuit control module plug ♦Measure voltage between PSM pin 2 and fuse F1 control module plug pin 2 and → End ground 2 Check signal lead of the ♦Switch on ignition < 0.3 V Short circuit to volt- booster pump for short ⇒ Step 3 age between PSM ♦Measure voltage between PSM circuit to voltage control module plug control module plug pin 4 and pin 4 and pin 1 of ground PSM booster pump plug → End 4503 Fault code 4480 45-31 page 1 Printed in Germany – 4, 2001 4480ps05