Fuel Tank Pressure Sensor (B4/3)

NOTE: Fuel tank pressure sensor (B4/3) is located inside fuel tank (with fuel level sender assembly).

Signal - Turn ignition off. Connect DVOM between right cylinder bank ME-SFI control module (N3/12) connector 1 terminals No. 53 and 52 (socket box terminals No. 53 and 51). Connect jumper wire between right cylinder bank ME-SFI control module connector 1 terminals No. 26 and 34 (socket box terminals No. 26 and 34). Connecting jumper wire will allow activation of activated charcoal canister shutoff valve (Y58/4). Disconnect purge control line (at vacuum tee) to activated charcoal canister. Vacuum tee connects both purge control valves to activated charcoal canister. Connect vacuum pump to purge control line. Turn ignition on. Observe DVOM. Voltage should be more than 3 volts. Apply approximately 25 mbar of vacuum to purge control line. Observe DVOM. Voltage should be less than 2.5 volts. If voltage is as specified, test is complete. If voltage is not as specified, possible causes are voltage supply problem to fuel tank pressure sensor (B4/3), purge control line to activated charcoal canister leaking, activated charcoal canister blocked or fuel tank pressure sensor (B4/3) defective. Repair as necessary. To check voltage supply to fuel tank pressure sensor (B4/3), go to next step.
Voltage Supply - Turn ignition off. Connect DVOM between right cylinder bank ME-SFI control module (N3/12) connector 1 terminals No. 53 and 44 (socket box terminals No. 53 and 44). Turn ignition on. Voltage should be 4.7-5.3 volts. If voltage is as specified, test is complete. If voltage is not as specified, possible cause is right cylinder bank ME-SFI control module (N3/12) failure. Repair as necessary.