JD X485 fuel pump not running

   / JD X485 fuel pump not running #11  
So there might be an F1, F2, F3, & F6 too? It would have been nice if JD had put in one fuse block. All I found in the owners manual were the ones on the key module, and I read the 12v plug has one too.
 
   / JD X485 fuel pump not running
  • Thread Starter
#12  
Z
Seems these are like fusible links along the wire.. puzzles me too. Found the 20 amp for the accessory plug, hangs loose on the two wires.

Checked out Spanners suggestion for voltage at the Fuel Pump Relay.. there is a connector (X21) from the pump relay to the Fuel pump that is hanging out and easy to get at (see pic of it disconnected) with pink wire connected to the pink/black wire.
The pink has battery voltage for about 2 sec after the key is turned on (same length of time that the service engine light comes on the instrument panel) then goes off.
Will have to look for the reason for that.

Think I will feed 12v to that pink/black wire to see if the fuel pump will run.. can then take that out of the equation.
Edit: Put 12v to the pink/black wire and fuel pump didn't function. So suspecting fuel pump needs replacing.
 

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   / JD X485 fuel pump not running #13  
03:45 am here so Good Morning.
Lets go back a step.
How are you measuring the fuel pump performance? ('Sound' or disconnecting the fuel line and watching fuel pump through?)

The K13 Fuel Pump Relay goes off after a second or two? (Measured at the X21 connector which is the 655 wire/30 terminal I suggested.)

But the K13 gets its power direct from the K12 EFI Module Power Relay beside it. (221 Red Live power 'In' and 230 Red 'Out' to power the K13.)

So, go back a step and check that the K12 isn't failing to 'Hold' in for more than a brief second or two. (Measure Voltage at the 221-Red first to prove the power supply and then at the 230-Red (30 terminal) 'output' when you turn the key switch 'On')

That K12 relay is controlled by the 560-Red wire. Where does that come from?? You can measure the voltage on that wire also.

All of these circuits share the 'Ground' through the 100-Black wire spliced with the 150 & 120. These are normally crimped splice connections. Check your Ground/Earth circuits also for continuity.

The K12 & K13 relays are identical and you can swap them over to check the K12 is/isn't working.
It's a standard relay configuration so your NAPA will have replacement relays if necessary, just probably without the shroud and clip retainer but fine for testing/confirmation purposes. (If you can't get to your JD dealer for a replacement easily.)
 
   / JD X485 fuel pump not running
  • Thread Starter
#14  
Measuring by sound.. always has made enough sound whenever turning ign key on.

Thanks
I will switch relays to see if that improves

If the fuel pump, the original part NLA and replacement is later assembly running just over $300. So want to know for certain it is, or isn't defunct.

Will get back with results.. you can take a nap while waiting.. ;)
 
   / JD X485 fuel pump not running #15  
Just off the Fuel Pump is a in line fuse .
 
   / JD X485 fuel pump not running
  • Thread Starter
#16  
Learned my pre-40000 s/n x485 has different set of relay's than post 40000. Part #AT75769 instead of AM123716.
Chasing down another new one as prefer to switch in a new one and not try moving existing ones around. There are three in the pre-40000 apparently and 4 of different style in the post 40000. Just more delay.. Have not removed seat and fender deck yet.. but if relays don't suggest a different problem, will change up to the new post 40000 fuel pump assembly.
 
   / JD X485 fuel pump not running #17  
Yes, the later S/n relays have all pins in a straight line whereas the earlier models have the traditional relay with pins in a 'T-cross pattern'.

Later model Fuel Pump has some subtle differences to be aware of. Harness connector is different. There is a short adaptor harness to make the connection work. #AM133839.

Also the original pump/sender has 5 x mounting screws. The later version is 8 x mounting screws. Check for hole-alignment and use the new rubber seal as a template to drill new holes required (if any) It's been some years since I did one but I think the 5-holes are an irregular pattern so some holes do correspond with the 8-holer.

I thought it may be possible to swap the actual pump from the new unit to the old unit?? (Hosepipe and clamps and the filter sock?) Check yours.

The filter sock in the tank will tell you whether you need to clean out the tank as well, while you have the fender-deck off and easy access.

Be aware of the little bracket holding the fender-deck underneath to the left Grab Handle - it stops you lifting the deck off. Unplug the tail-lights if you have them fitted also but don't loose the sealing felts/rubbers around the bulbs.

Seat and runners come off first. Make sure the clips underneath are there before you refit the fender afterwards!

Hoping you don't have to do all this and that a relay or two will solve your problem. Off to work now but tuned in via the TBN App.
 
   / JD X485 fuel pump not running
  • Thread Starter
#18  
After exchange, now have the correct relay.. but a dinner party tonight will keep me occupied until tomorrow morning.. thanks for the help.. some I knew, but some I'll be finding out I'm sure. Good to have the heads up.
Relay differences that you mention.
 

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   / JD X485 fuel pump not running #19  
Yes both have 5-pins and they are numbered the same so you can make jumper wires to adapt the newer one if desperate.

The change is an annoying result of the automotive industry move to smaller pins and fuses etc.

Enjoy your dinner!
 
   / JD X485 fuel pump not running #20  
Two more relays to check.
K5 which is the IGN Relay on the Ignition interlock module. It powers K11, which is the Module Ground relay for the Fuel Injection Module.
Both needed for the fuel pump to run.
 
 
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