FUEL WARNING MESSAGE

[Tony Clark]

Geoff, did you check the fuel filter that protects the transfer pump from blockages?

Tony

[GeoffW]

No, I didn't see a fuel filter, but the inside of the tank was spotless.  The pump wasn't running - blocked filter or not.

Geoff

[GeoffW]

Photo below showing remotely mounted relay for sub pump and switch to connect relay coil to earth when required.  The earth connection for the switch was found using a test light in an empty relay socket just near where the relay is now mounted.  You can trace the solid black wire.  Btw, I soldered all the crimp connectors.  I don't have a lot of faith in crimp connectors.

Geoff

Edited June 2 by GeoffW

[KangaRooted]

Glad you got it sorted Geoff.

I think I got a win on mine too.  I ended up replacing the entire unit inside the fuel tank.  The pump was working but was very sick sounding.  Also, the filter was very dirty too.  I supposed it's to be expected after 14 years. What I can say is that I think some fuel was being pumped from the rear tank, but I think between the filter and the sick pump, it was not enough to empty the rear tank could empty quick enough.  

Maybe replacing the filter could have gotten me over the line, but I didn't want to have to do the job again.  Perhaps if I was selling the car, I might have a different opinion. Its half a day that I won't forget anytime soon.  I think I ended up with more diesel on me than on the ground....

 

[GeoffW]

Yes, it's a ***** of a job.

[campbeam]

6 hours ago, KangaRooted said:

Glad you got it sorted Geoff.

I think I got a win on mine too.  I ended up replacing the entire unit inside the fuel tank.  The pump was working but was very sick sounding.  Also, the filter was very dirty too.  I supposed it's to be expected after 14 years. What I can say is that I think some fuel was being pumped from the rear tank, but I think between the filter and the sick pump, it was not enough to empty the rear tank could empty quick enough.  

Maybe replacing the filter could have gotten me over the line, but I didn't want to have to do the job again.  Perhaps if I was selling the car, I might have a different opinion. Its half a day that I won't forget anytime soon.  I think I ended up with more diesel on me than on the ground....

 

After the event, you realise that it is a real labour of love. Past pleasure and lots more pleasure to keep on coming in the future.

[Tony Clark]

Geoff,

I have a fuel blockage in my Prado. Both tanks are full but no fuel flows to the Injector pump.

Is there a filter or strainer in the main fuel tank:

How does the electrical connector for the Fuel sender assembly disconnect?
I have posted this tonight - - - -

 

 

[Rusty Olds]

On 7/7/2024 at 9:33 AM, KangaRooted said:

Glad you got it sorted Geoff.

I think I got a win on mine too.  I ended up replacing the entire unit inside the fuel tank.  The pump was working but was very sick sounding.  Also, the filter was very dirty too.  I supposed it's to be expected after 14 years. What I can say is that I think some fuel was being pumped from the rear tank, but I think between the filter and the sick pump, it was not enough to empty the rear tank could empty quick enough.  

Maybe replacing the filter could have gotten me over the line, but I didn't want to have to do the job again.  Perhaps if I was selling the car, I might have a different opinion. Its half a day that I won't forget anytime soon.  I think I ended up with more diesel on me than on the ground....

 

Hi guys,

I now have this issue.  We are away in WA and NT when this issue occurred, I came very close to running out of fuel (still a quarter on the gauge) before I could get signal to investigate and also get fuel. It could be a critical issue when towing the caravan and you suddenly find yourself with substantially reduced range. 
 

thanks Geoff and Steve for your valuable information. Steve could you please let me know exactly where the sub tank fuel filter is, I suspect that might be my first point to check. 

[GeoffW]

Gary

My first problem occurred on a trip to WA.  I ran out of fuel just out of Port Augusta.  Not then knowing what the problem was, I again ran out of fuel just out of Ceduna.  It was there that I researched the problem.  I continued on to WA thereafter just using the main tank of 90 litres and refilling when down to 1/4 full.  I had no problems getting around WA for the next 2 months towing a 3.5 tonne van.  Plenty of fuel spots.

Geoff

[Rusty Olds]

It’s not going to be hard to get around now that I know. like you I will just have to top up more often. I’m sure glad that I didn’t run out of fuel like you. 
 

Yesterday I checked the relay contacts for earth and found that the negative had some resistance, so I have fitted a jumper wire to an empty relay spot earth connection. Maybe it will help, maybe not, I’m still trying to figure what the exact issue is. 
 

Another question if I may, did you also have issues getting full fuel into the tank? Twice now I’ve filled up (can’t get any more in) and when I’ve started the car afterwards the gauge has shown just over 3/4. Makes me wonder if I have a venting problem with the sub tank. 
 

 

[GeoffW]

Yes, I had that problem, too.  A full sub-tank sometimes seems to impede the filling of the main tank.  What I found was that if you keep putting fuel in until click off, and then do it again and again, you can eventually fill the main tank.  That fact that it only happens sometimes would indicate to me that the angle of the vehicle might have something to do with it.  If you were to run the vehicle into the bowser from the opposite direction, it might solve that problem.

Note, when testing the +12V or ground of various fuse box connectors be wary of high impedance modern multimeters.  I found that a small 12v test light (incandescent, not LED) gave better results.

Geoff

[Rusty Olds]

Thanks Geoff. The fact that I have had issues fueling only a couple of times would seem to indicate that you are right, though it has only happened after I’ve had the warning (if I don’t get the warning then it fills ok). I’ll see how it goes. 
 

when I get home I’ll put her up on the hoist and have a good look. 

[Rusty Olds]

Well it seems that my earth “jumper” wire didn’t work. I will just have to live with it for the next few weeks until I can put it up on the hoist. 

[GeoffW]

Rusty, Is there a replaceable filter in the bottom of the transfer pump?  I never got to see it.   But, the inside of my tank was spotless so I didn't suspect a filter issue.  Remember, if you can get the pump to work, you can definitely hear it (with engine stopped).  So, it would be wise to eliminate electrical problems first.  Putting +12v into the hole in the relay socket that connects to the pump should run the pump if it has a good earth.  If a good pump doesn't run with +12v, you should then check the earthing of the pump.  I don't know where it earths, but the other power wire from the pump socket (on the tank) must go to earth.

See circuit diagrams attached.  Note: there are 2 images.  One is visible in this posting, the other is a PDF file for which you will need a PDF reader to open.  You might have to expand the image it to be able to read it.  It's not suitable for reading on a phone.  The +12v for the relay coil comes from the EFI relay.  The 12v for the sub pump comes directly from the battery through a 20A fuse.  The earth for the sub pump connects directly to ground somewhere.   As I suspected earlier, the earth for the sub-pump relay coil is controlled by the ECU. 

Geoff

ECS-1VD.pdfECS-1VD.pdfECS-1VD.pdfECS-1VD.pdf

Edited August 10 by GeoffW

[Rusty Olds]

Thanks Geoff, great stuff. I’ll just keep going until I get home in a couple of weeks. I will be in a much better environment (my shed, with concrete and hoist, etc, etc) when I get home. I’m not going to look at it while knee deep in dust, 🤣😂.
 

Once I have worked out what the problem is then I will let you know. 
 

by the way, it seems that you can buy just the new pump itself without having to buy the whole assembly. I’ve done a few in tank pumps before with petrol driven cars and I’ve found a you tube on it for the LC200. 

[Rusty Olds]

Thanks Geoff, great stuff. I’ll just keep going until I get home in a couple of weeks. I will be in a much better environment (my shed, with concrete and hoist, etc, etc) when I get home. I’m not going to look at it while knee deep in dust, 🤣😂.
 

Once I have worked out what the problem is then I will let you know. 
 

by the way, it seems that you can buy just the new pump itself without having to buy the whole assembly. I’ve done a few in tank pumps before with petrol driven cars and I’ve found a you tube on it for the LC200. but I will be looking at the electrical side of things first.