Help, fuel pump electrical diagnosis (1995 2WD)
#1
Fuel pump 12v direct test?
Dear friends
I own a Blazer 1995 2WD that the fuel pump stop working. Would not energize as always (no sound) when initially turn switch on. Good cranking but no engine start.
Fuse and relay are fine.
Took tank down and now pump is out. Nothing broken in plain view
Question: Can I apply 12v directly to the pump connectors in the pump to confirm that the pump is the problem and not lack of electric power?
Thanks. Carlos
I own a Blazer 1995 2WD that the fuel pump stop working. Would not energize as always (no sound) when initially turn switch on. Good cranking but no engine start.
Fuse and relay are fine.
Took tank down and now pump is out. Nothing broken in plain view
Question: Can I apply 12v directly to the pump connectors in the pump to confirm that the pump is the problem and not lack of electric power?
Thanks. Carlos
#2
If the pump is out it is not recommended to run it dry although I have but..why not put 4 cotter pins in the pigtail and test it with a 12v test light..should be 4 wires...2 grounds (check them both) and a 12v and a 5 volt signal (for the gauge)..good luck! Jerry
#3
Will try it that way. Thanks a lot Jerry
#4
I connected the pump directly to batt and pump worked ok. It expelled remaining fuel in the pump with force. Hooked 12v tester to underchassis connector that goes to the pump and is not getting current when turning key. Cable bundle plastic cover is in good shape,no cuts etc till connectors under the hood, those connectors also look fine. From there on i loose sight where the grey cable goes. Fuse and relay (exchanged to horn site and horn worked) are fine. Planning to check current at fuse box and relay ( not sure if there is a click or not). Do you know the basic fuel pump electric circuit? That grey pump cable should end in the computer?
Thanks very much
Carlos
#5
Dear Jerry and friends, need help with diagnosis of fuel pump electrical supply
I own a Blazer 1995 2WD that the fuel pump stop working. Would not energize as always (no sound) when initially turn switch on. Good cranking but no engine start.
Fuse and relay tested fine.
Took tank down, remove fuel pump and hooked fuel pump directly to the battery and worked fine. Ejected remaining fuel at the pump with force.
Placed 12v tester at pigtail connector (grey wire is +) hanging under chassis and no voltage when ignition switch turned on.
Went to glove compartment and no voltage is getting to pump relay when switch turned on.
My diagnosis is fuel pump is not getting voltage.
Q?
If pump relay in the glove compartment is not getting 12 v, where is the voltage for the relay coming from? where should I test next to find where is the current interrupted?
(Don't have an electrical diagram)
Thanks a lot
Carlos
I own a Blazer 1995 2WD that the fuel pump stop working. Would not energize as always (no sound) when initially turn switch on. Good cranking but no engine start.
Fuse and relay tested fine.
Took tank down, remove fuel pump and hooked fuel pump directly to the battery and worked fine. Ejected remaining fuel at the pump with force.
Placed 12v tester at pigtail connector (grey wire is +) hanging under chassis and no voltage when ignition switch turned on.
Went to glove compartment and no voltage is getting to pump relay when switch turned on.
My diagnosis is fuel pump is not getting voltage.
Q?
If pump relay in the glove compartment is not getting 12 v, where is the voltage for the relay coming from? where should I test next to find where is the current interrupted?
(Don't have an electrical diagram)
Thanks a lot
Carlos
#6
Help, fuel pump electrical diagnosis (1995 2WD)
Dear Jerry and friends, need help with diagnosis of fuel pump electrical supply
I own a Blazer 1995 2WD that the fuel pump stop working. Would not energize as always (no sound) when initially turn switch on. Good cranking but no engine start.
Fuse and relay tested fine.
Took tank down, remove fuel pump and hooked fuel pump directly to the battery and worked fine. Ejected remaining fuel at the pump with force.
Placed 12v tester at pigtail connector (grey wire is +) hanging under chassis and no voltage when ignition switch turned on.
Went to glove compartment and no voltage is getting to pump relay when switch turned on.
My diagnosis is fuel pump is not getting voltage.
Q?
If pump relay in the glove compartment is not getting 12 v, where is the voltage for the relay coming from? where should I test next to find where is the current interrupted?
(Don't have an electrical diagram)
Thanks a lot
Carlos
I own a Blazer 1995 2WD that the fuel pump stop working. Would not energize as always (no sound) when initially turn switch on. Good cranking but no engine start.
Fuse and relay tested fine.
Took tank down, remove fuel pump and hooked fuel pump directly to the battery and worked fine. Ejected remaining fuel at the pump with force.
Placed 12v tester at pigtail connector (grey wire is +) hanging under chassis and no voltage when ignition switch turned on.
Went to glove compartment and no voltage is getting to pump relay when switch turned on.
My diagnosis is fuel pump is not getting voltage.
Q?
If pump relay in the glove compartment is not getting 12 v, where is the voltage for the relay coming from? where should I test next to find where is the current interrupted?
(Don't have an electrical diagram)
Thanks a lot
Carlos