Was changing fuel pump and did not get power to it so I started checking fuses, then relays. All good. I decide to check the pump one more by jumping the B+ and FP in the diagnostic port. No power to the B+ in the OBD port. Not in crank or run positions. What are the most common causes?
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As I said all fuses have been checked. The fuse you speak of, the glove box has to be removed. According to the diagram the heater relay a/c 10 amp and heater 30 amp fuses are there, and I have checked them.Been using Clinton repair manual for guidance. Any other suggestions?
Fuel pump *RELAY* is under passenger side dash.
The air vane inside the top cover of the air cleaner is what actuates the fuel pump when engine is CRANKING - you can remove the top cover and reach in there with your finger and manually move that air vane - with key ON the pump circuits are closed and pump should turn on.. You will also be able to hear the fuel pump relay click on - the engine does NOT have to be cranking for this test.. This is the most accurate and reliable method of fuel pump and circuit testing.
The fuel pump RELAYS are prone to failure while the fuel pumps are not !
Good luck with it!
NOTE: : The repair manual is likely calling this relay the CIRCUIT OPENING RELAY instead of the actual fuel pump relay as it should be labeled..
During the suggested test - IF you DO NOT hear the relay click on there is an open circuit TO the relay ... IF the relay DOES click on but pump DOES NOT turn on - there is an open circuit from relay TO the pump...
The relay may be behind the passengers kick panel.
This concludes my “OTHER SUGGESTIONS”..
▪️ RELAY MAY BE LOCATED BEHIND PASSENGERS KICK PANEL ▪️
I’ve been retired for a while now - impossible to recall the exact details for all the stuff I have worked during the 46 years in the business..
Just move the air vane with key ON and see what happens..
Listen closely for relay click and fuel pump operation - in a quiet environment you’ll be able to hear both.
Additionally - the actual fuel pump relay is pretty well hidden under passenger side dash.. Good luck!
As I said all fuses have been checked. The fuse you speak of, the glove box has to be removed. According to the diagram the heater relay a/c 10 amp and heater 30 amp fuses are there, and I have checked them.Been using Clinton repair manual for guidance. Any other suggestions?
Fuel pump *RELAY* is under passenger side dash. The air vane inside the top cover of the air cleaner is what actuates the fuel pump when engine is CRANKING - you can remove the top cover and reach in there with your finger and manually move that air vane - with key ON the pump circuits are closed and pump should turn on.. You will also be able to hear the fuel pump relay click on - the engine does NOT have to be cranking for this test.. This is the most accurate and reliable method of fuel pump and circuit testing. The fuel pump RELAYS are prone to failure while the fuel pumps are not ! Good luck with it!
NOTE: : The repair manual is likely calling this relay the CIRCUIT OPENING RELAY instead of the actual fuel pump relay as it should be labeled.. During the suggested test - IF you DO NOT hear the relay click on there is an open circuit TO the relay ... IF the relay DOES click on but pump DOES NOT turn on - there is an open circuit from relay TO the pump... The relay may be behind the passengers kick panel. This concludes my “OTHER SUGGESTIONS”..
▪️ RELAY MAY BE LOCATED BEHIND PASSENGERS KICK PANEL ▪️ I’ve been retired for a while now - impossible to recall the exact details for all the stuff I have worked during the 46 years in the business..
Thanks for your help will let you know how it goes. Thanks again.
Just move the air vane with key ON and see what happens.. Listen closely for relay click and fuel pump operation - in a quiet environment you’ll be able to hear both.