Need help with LRA wiring (1 Viewer)

[kcjaz]

I have had my 24gal LRA moved from my old 200 to the new one. I did not personally do the install either time so I don't know what the wiring at the tank actually looks like. Here is the diagram from the install instructions:

My current issue is that the pump does not run and I do not have any voltage at the pump terminals with the pump switch on. The sender seems to be working as the level indicator on the in cabin switch is lit up and working. When I push the transfer button the yellow indicator light lights up indicating the pump is running but it isn't (its really just showing the switch is closed). There are only two wires that go through the firewall from the switch (yellow and white shown above). the original install shop ran the two wire cable through the firewall and then under the truck to the tank. Before we moved the tank to the new 200, I moved the in cabin wiring and switch over to the new 200 and installed a two wire male/male connector under the hood so we could reconnect the wires when the tank was moved.

What I don't know and can't tell from the wiring diagram is what is really supposed to be physically connected at the tank. The diagram seems to show the yellow wire going directly from the switch to the pump and only the white wire going to the sender unit. I have 12v at the new under hood connector (I disconnected it at tested with meter) but not at the pump (when connector is connected). The other wire has no volts with plug disconnected as I would expect.

For the sender to work in must need power and, in my mind anyway, there must be a connection from the yellow wire to the sender that isn't shown in the diagram so that the sender has a circuit to send back the voltage signal to the gauge in the dash. If that is correct, then my guess is that the wire I can see at the pump isn't connected at the sending unit. I suspect that the yellow wire goes to a screw/lug on the sender and there is supposed to be a short wire run from there to the pump. I'm guessing we just connect that wire when we moved the tank and pump. Can anyone who has doe this themselves confirm this?

If I'm right, its a bummer because I think I'll have to drop the tank to get to the sender.

 

[TeCKis300]

IIRC, the wiring is as depicted and there weren't any surprises.

Yes, a single white wire to the sender from the switch. With a local ground near the tank.

Same with the pump, single yellow wire to pump from switch, with a local ground at pump.

Here's maybe some more resources. It's an Apexus PG210 swtich.

 

[kcjaz]

IIRC, the wiring is as depicted and there weren't any surprises.

Yes, a single white wire to the sender from the switch. With a local ground near the tank.

Same with the pump, single yellow wire to pump from switch, with a local ground at pump.

Here's maybe some more resources. It's an Apexus PG210 swtich.

Thanks. So for the white wire going to the sender, shouldn’t I see 12 v or at least some voltage at the switch? Essentially the level gauge is an ohm meter with one lead connected to ground and the other going from the battery, via an ignition circuit, to the 0-90 ohm resistor.

I do not have voltage on both wires coming from the switch. Maybe the one I think is the sender (dead one) is really the pump. I can’t tell wire color because of sheath and heat shrink. Seems like it’s another self inflicted wiring issue.

 

[TeCKis300]

Thanks. So for the white wire going to the sender, shouldn’t I see 12 v or at least some voltage at the switch? Essentially the level gauge is an ohm meter with one lead connected to ground and the other going from the battery, via an ignition circuit, to the 0-90 ohm resistor.

I do not have voltage on both wires coming from the switch. Maybe the one I think is the sender (dead one) is really the pump. I can’t tell wire color because of sheath and heat shrink. Seems like it’s another self inflicted wiring issue.

Good question and definitely a possibility that the two leads are mixed. I can't say what the voltage output on the sender line is, depends on implementation. But could be something really small maybe in the 1V range. You can try grounding that line to see if the meter reads empty?

 

[kcjaz]

Finally got back to this and figured it out. The original installer had added a relay to power the upgraded pump we installed. He used an add-a-fuse to add the relay circuit. The issue was just that somehow when I moved all the wiring over, I must have pulled the fuse from the add-a-fuse and put it back in the wrong slot. Essentially, I had a missing fuse in the power circuit to the pump. Simple fix but took me hours to figure out as I am electrically challenged.