Fuel Pump; Fuel Pump Operation; Hold Pressure - Mazda MX-5 1990 Workshop Manual

FUEL SYSTEM
F
FUEL PUMP
Caution
• Obtain the code number and deactivate the audio
anti-theft system before disconnecting the battery.
(Refer to page T -113.)
Inspection
Fuel pump operation
1. Connect the diagnosis connector terminals F/P and GND
with a jumper wire.
2. Remove the fuel filler cap.
3. Turn the ignition switch ON.
4. Listen for operational sound of the fuel pump at the filler inlet.
5. Install the fuel filler cap.
6. If no sound was heard, measure the voltage between the
fuel pump connector wire to ground.
Voltage: 12V
7. If not correct, check the circuit opening relay and its cir-
':' cuits. (Refer to page F-109.)
05UOFX-145
05UOFX-146
8. If the voltage is normal, check for continuity between fuel
pump connector (8) and a ground.
9. If there is continuity, replace the fuel pump.
10. If no continuity, repair the ground circuit.
Hold pressure
Perform this inspection if the fuel pressure hold inspection is
not as specified. (Refer to page F-102.)
Warning
• Before performing the following operation, release
the fuel pressure from the fuel system to reduce the
possibility of injury or fire. (Refer to page F-101.)
1. Disconnect the negative battery terminal.
2. Connect a fuel pressure gauge to the fuel main pipe and
plug the outlet of the fuel pressure gauge as shown. (Install
clamps as shown.)
3. Connect the negative battery terminal.
F-107