zinger11

Hi, everyone!

Could someone please tell me where the fuel pump relay is located on a 2010 G37x sedan? I'm assuming it's in the IPDM next to the starter control relay, but I have not been able to verify that in the FSM. Call me crazy, but I literally searched the string 'fuel pump relay' in every section of the FSM; all 57 PDFs!

Thanks so much!
zinger11

G37Sam

Off topic, but why do you need to find it?

zinger11

No problem! I am fixing up a salvage G37x to use as my daily driver. The car is just about ready to go, but it will not start. It cranks, but never starts. The fuel pump never comes on. I tested continuity from the IPDM all the way back to the fuel pump, and it tested good. I also sent a voltage down that same wire, back to the fuel pump, and it turned on, so I know the wiring is good and the fuel pump is good. According to the FSM, now the problem has to lie between the IPDM, fuel pump relay, and/or ECM.

I wanted to start with the easiest thing first, so I am trying to get the location of the fuel pump relay. There is one unmarked relay in the FSM (which lies in the IPDM), so I am assuming it's the fuel pump relay.

Any ideas? Thanks!
zinger11

G37Sam

Aaah I see, thanks for the clarification

Here's something that may be of help:
http://www.infinitig37.com/TSB/1SA22.pdf

zinger11

G37Sam, thanks for the info.

If anyone is interested, I have an update on the car...

After following the step-by-step troubleshooting guide in the FSM, I was brought to the solution of "replace IPDM." All of my car's wiring was sound, the fuel pump worked (when supplied with an external voltage), continuity to the ECM from the fuel pump harness was verified. I'm thinking the problem may be the fuel pump relay. Again, assuming the fuel pump relay is located inside the IPDM, that makes perfect sense (since the fuel pump relay is literally the only relay that I have not found). Either the relay is bad or, as the FSM states, the IPDM is bad.

However, I did actually get the car to start! I hooked up all of the connectors, and ran a separate wire to power the fuel pump. The car fired right up (and sounded GREAT BTW)! I have nothing to lose, so I may try to take apart the IPDM and see what's up. Worst-case-scenario, I buy a new IPDM. I can live with that.

Thanks to everyone for helping me with my project. It's been a taxing adventure, but I think it will be worth it in the end. I hope some of my posts will help others who may have similar issues. Feel free to PM me with any questions about the fuel pump, wiring, or IPDM. I'd be glad to help troubleshoot a problem (based on what I've gone through with my car).

Regards,
zinger11

JohnnyGswag

I have the same problem!........

G37Sam

Do you buy any chance have the wiring diagram of the fuel pump and its relay?

zinger11

G37Sam,

I do not have the wiring diagram for the fuel pump & relay handy; I just got the entire Factory Service Manual from Fezzik's post here - https://www.myg37.com/forums/g37-sed...for-sedan.html - and clicked through until I found what I needed.

Also, the main issue with my car was a bad ECM. I initially thought fuel pump/wiring/relays were bad, but it turned out the ECM wasn't supplying a voltage to the pump to get it going.

Best of luck!
zinger11

Tony RosCoe

can someone tell me whats up with fluctuating fuel gauge. its getting really annoying having to go to the gas station to find out that im not out of gas. and vice versa making feel gas is in the tank. not sure if its a fuel pump issue just trouble shooting right now. HELP!!!!!!

camopaint0707

did you ever solve the issue? was it the relay?

zinger11

camopaint0707,
My issue was resolved, but it was not the relay or fuel pump. My ECM was bad, so I picked up a used one that worked perfectly. I was definitely chasing my tail on that issue, so if you're getting nowhere in your troubleshooting, always remember to test your ECM; it could be that. Best of luck!
-zinger

camopaint0707

stupid question, but how do I test my ecm?

zinger11

Ah, no worries...there is no such thing as a stupid question!

You may want to check out sites like ecmtogo.com. They offer testing and repair services for ECMs. Also, for one of my other vehicles that I thought was having an ECM issue, I ended up posting on a related message board asking if anyone would be willing to lend me their working ECM to test in my car. To my surprise, someone loaned me theirs (and as it turned out, that person is still to this day a great friend of mine). My ECM was bad, so I sent it in to ecmtogo.com for repair and they rebuilt it.

Good luck!
-zinger

camopaint0707

Well damn, I guess I can start looking there. I'm pretty sure my pump isn't getting power.

13_SkylineSedan

Really, the place to start might be the Factory Service Manual. If you don't have them already go here:
https://www.nicoclub.com/infiniti-service-manuals
Scroll down, click "G35 / G37 / Q40", click "G37", click "Coupe" (if that's what you're driving), click the year, click "Power Supply, Ground and Circuit Elements". Then scroll down below the window displaying the manual and "Click here to download a copy".

These books are not very easy to read but this one has all the info about your car's electrical systems and will help you troubleshoot power, ground, fuses, relays, etc..