Fuel Pump Relay Pinout (1 Viewer)

[mklemp]

Hey team, I've got a no power condition to the fuel pump. I've checked all of the fuses and relays and I'm down to the fuel pump relay. Does anyone have a pinout of this relay so that I can bench-test it?

 

[elripster]

I'll check my schematics. You should have voltage on 2 of the plug side pins and ground.

Frank

 

[Malleus]

Do you have the EWD? If not, there are copies for free download in the Resources section which have the pinouts for every device in the truck.

 

[elripster]

Did you check for continuity at the AFM? The flapper door has to move to enable power to the fuel pump (lower left...)

 

[elripster]

I'd second getting the manuals. This is for OBD1, not sure what year your truck is.....

 

[SmokingRocks]

download yourself a free gift called the Factory Service Manual (link in my sig) seriously its like the best cookbook ever. I've used it hundreds of times to bake up so many tasty fixes.

 

[mklemp]

Did you check for continuity at the AFM? The flapper door has to move to enable power to the fuel pump (lower left...)

View attachment 3271190

Thank you for this schematic and the AFM detail. I'll check it out and report back.

 

[SmokingRocks]

And download your FSM!!! And save it to your computer, your Google drive, your moms computer, burn it to a cd and put it on a shelf. It’s a must have

 

[elripster]

And download your FSM!!! And save it to your computer, your Google drive, your moms computer, burn it to a cd and put it on a shelf. It’s a must have

I couldn't agree more. I have this on my google drive set to access offline so it synchs to my phone, tablet, computer... etc.... It's the only way especially if you need it when out of cell range.

Frank

 

[mklemp]

Found this test procedure in the FSM for the Fuel Pump Relay. Mine is good so on to other tests.

 

[SmokingRocks]

boy look at that, its like they thought about how to troubleshoot this issue and put it on paper! and its easily downloadable through the link in my signature?! well slap my ass and call me sally that's as good as it gets.

In all honesty it took me about 3 years of wrenching on my cruiser to fully trust the troubleshooting in the FSM, after burning hours doing needless test and replacing totally fine components I learned that the test in the FSM are truly on the diagnostic tree that you should follow.

 

[1barubier]

I'd second getting the manuals. This is for OBD1, not sure what year your truck is..... View attachment 3271213

Thanks for the diagram. will check it out.

 

[mklemp]

My truck is a late 1995 so it has OBD2. There are no codes reported and this circuit diagram for the fuel pump is a bit different. This circuit has a an FP pin on the check connector which makes it easy to check for voltage at the fuel pump. I have this connector and it has a spot for a pin labeled FP, but there is no physical pin and connection at the FP location.

 

[Malleus]

All '93-'97 Land Cruisers have the "DLC 1" port at the firewall; the OBDII port is "DLC 3" on the EWD (I've yet to find DLC 2). The FSM troubleshooting instructions still recommend the DLC 1 port for some functions on the OBDII models.

My JAN'95 doesn't have it either (or the Gen terminal, so I can't check ECU rpm input ). Sucks to be us.

I attached the '95 Fuel pump relay and resistor checks. There isn't a similar, simple, ECU/system check as with the OBDI models on the OBDII models.

I attached the very long, laborious system check procedure for you.

 

[mklemp]

All '93-'97 Land Cruisers have the "DLC 1" port at the firewall; the OBDII port is "DLC 3" on the EWD (I've yet to find DLC 2). The FSM troubleshooting instructions still recommend the DLC 1 port for some functions on the OBDII models.

My JAN'95 doesn't have it either (or the Gen terminal, so I can't check ECU rpm input ). Sucks to be us.

I attached the '95 Fuel pump relay and resistor checks. There isn't a similar, simple, ECU/system check as with the OBDI models on the OBDII models.

I attached the very long, laborious system check procedure for you.

Gracias and perfect timing for weekend troubleshooting.

 

[Malleus]

de Nada