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Discussion Starter · #1 ·
My trusty 2010 with a 2.0 "I' version has to been starting good. I thought it was the fuel pump as it wasn't getting the 12 volts to make it come on.
Tracked back to checking the relay and it was not "clicking" in a change of state. I jumped the relay power terminals and the pump came on. I verified the voltage at the relay base and have 12.3 volts when I turn the key on. I tried swapping the relay and the swapped one wouldn't change states either.
I'm going to try to connect the power terminals via a jumper to the base. I'll take the ground side directly to the battery ground and apply power. If it doesn't change I'll then take the ground side back to the base and apply battery power to the other side of the relay. (I have verified the relays change state when jumped to the battery (+ & -) directly.)
Any help on this is appreciated!
Thanks
 

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Discussion Starter · #2 ·
What would the power side of the relay base positive lead has some .877 megaOhms. Is this correct? The battery is at 12.02 volts, and power drops to 11.71 at the terminal with the power on.
 

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From what you wrote it sounds like you have confirmed good voltage at both the pump power side and the control side of the relay, and also that the pump spins when the relay control side is bypassed. If so, then the problem must be no ground being received from the PCM at the relay control side. And you can easily confirm that by wrapping a jumper wire around the control side ground pin, pushing the relay back down into the socket, and then touching the other end of that wire to any ground. Be VERY careful to not leave any wire strands loose, which could possibly come in contact with other relay pins!

This test should enable the vehicle to start and run as long as that jumper stays grounded. Assuming it does, then the next thing to diagnose is if the PCM is not sending the ground, or if a good ground signal from the PCM is getting messed up in the fuse box, or external wiring. Post back if you're able to get that far, and we'll see what might come next.
 

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you must repair the ecu ground correctly
do not leave it permanently grounded as in an accident ecu will not be able to shut off fuel pump
 

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I clearly described this ground jumper to be just a test, and made no suggestion that it should be used as a permanent repair. If the OP comes back with a reply, then the next step will be to remove the jumper and continue the diagnosis.
 

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m3i, i wasn't having a shot at you
but as you know on forums
once the car starts most users never come back
as op only has two posts, i was worries that he would make a permanent ground and next we heard from him was when he was on the night time news
 

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Certainly a valid point there lout, and hopefully this OP is not someone who would actually turn the test into a permanent fix!
 

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Discussion Starter · #8 ·
[I was able to locate an iffy wire that had rubbed almost in to two pieces. Now that’s good, and I replaced the fuel pump with a known good one. All that works. (Note: the vehicle sat for two years. Prob better pour some newer fuel in it too)
Cranks but no start. Spark is there, have hot checked the injectors. But it won’t run by spraying brake cleaner in whilst cranking. Going to check injection and prob better do a compression check. It’s a 2.0 and should be 190-200 psi?I’ll keep the forum updated as I make progress.
Thanks for the forum help.
QUOTE="lout, post: 10160349, member: 2582625"]
you must repair the ecu ground correctly
do not leave it permanently grounded as in an accident ecu will not be able to shut off fuel pump
[/QUOTE]
 
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