Help: 2002 LC Fuel Pump priming while key inserting causing battery drain (1 Viewer)

[CLEM3]

Good evening folks,

Hope everyone’s having a good day. I’m having an issue on a newly bought 2002 Land Cruiser. The issue is whenever I insert the key the fuel pump automatically turns on and starts priming. This has caused the car to drain the battery while simply having the key inserted over a short period of time. If anyone has any solutions or things to check first that’s be greatly appreciated!

Thanks,

Cle

 

[Dirt J]

I'm pretty sure the fuel pump only runs when cranking, not at key on.

What makes you think the fuel pump is running? There is a hum at key on but that is the brake system.

 

[Trunk Monkey]

The fuel pump runs for a moment to prime when you turn the ignition to on, but then shuts off until you crank. OP are you talking just inserted into the keyway or when it's turned to "on"?

 

[3_puppies]

Good evening folks,

Hope everyone’s having a good day. I’m having an issue on a newly bought 2002 Land Cruiser. The issue is whenever I insert the key the fuel pump automatically turns on and starts priming. This has caused the car to drain the battery while simply having the key inserted over a short period of time. If anyone has any solutions or things to check first that’s be greatly appreciated!

Thanks,

Cle

reading this, are you saying just having the key in the ignition, not rotating it, the fuel pump is turning on?
and it just stays on, never shutting off with the key in the ignition until the key is removed?

 

[Hugh Heifer]

I believe the noise that we hear and feel when we turn the truck to on before start is the brake booster motor, no?
But if there is something going on with the key just inserted there are other issues.

 

[CLEM3]

reading this, are you saying just having the key in the ignition, not rotating it, the fuel pump is turning on?
and it just stays on, never shutting off with the key in the ignition until the key is removed?

I believe the noise that we hear and feel when we turn the truck to on before start is the brake booster motor, no?
But if there is something going on with the key just inserted there are other issues.

I'm pretty sure the fuel pump only runs when cranking, not at key on.

What makes you think the fuel pump is running? There is a hum at key on but that is the brake system.

Sorry for the confusion. The fuel pump is actually priming while the key is just inserted not even rotated or switched to the “on” position. I have removed the fuel pump relay while the keys inserted and it stops. Which lead to believe the oil pressure sensor was reading high causing the pump to prime. But even unplugged the pump still ran.

 

[Hugh Heifer]

I do not know if it is a possibility but there has been some issues linked to the actual ignition switch. In my case, key out, I got an incessant clicking of a relay under the hood. Key in, no clicking. For others, the replacement of the switch only ( a $20 part) fixed that issue. While it certainly sounds like this is completely different, I just wanted to throw that out there. Mine actually turned out to be a bad ECU. Never was wet - just died. If the ECU gets wet, and they sometimes do because of the location of the sunroof drains, all kind of weird stuff can happen.
There is some stuff about some of that here.
Have you tried to read the codes to determine if there is anything going on there?

 

[CLEM3]

I do not know if it is a possibility but there has been some issues linked to the actual ignition switch. In my case, key out, I got an incessant clicking of a relay under the hood. Key in, no clicking. For others, the replacement of the switch only ( a $20 part) fixed that issue. While it certainly sounds like this is completely different, I just wanted to throw that out there. Mine actually turned out to be a bad ECU. Never was wet - just died. If the ECU gets wet, and they sometimes do because of the location of the sunroof drains, all kind of weird stuff can happen.
There is some stuff about some of that here.
Have you tried to read the codes to determine if there is anything going on there?

Haven’t gotten any codes related to the issue. I’m starting to think the motor was swapped from an early Lexus 2uz by the looks of the Knock sensors and intake manifold gaskets. While pulling the manifold I saw that “sequoia” was written on it, probably from a junkyard… Still have some more digging to do. I’m almost certain the motor was swapped and thrown together horribly. But I’ll keep updating.

 

[2001LC]

Look at/for VIN # BK 2 head, center, just below head cover. Missing would be clue a replacement engine. But the wire harness looks 100 series, which would have to be. There are a number of signs I look for, showing sloppy engine swap. I can't see those in picture.

BTW: I see what looks like coolant leak at rear water bypass joint pipe to heater Tee. The pipe if to much side to side pressure on it, will leak at base where pressed in. This happens during heater Tee & hose replacement. It may just be coolant spill and not cleaned during heater Tee service, I can't tell from picture.

In a 2002 LC it is very limited what gets power, with key just in. You should see security light (center dash console) go off as key inserted. Which confirms you've a master key and working immobilizer system. But this should not be enough, to drain battery over short period. Even if fuel pump getting continuous power, which should it not be.

First, I'd be taking a look at battery condition, it's post & clamps and alternator as first step. As you should not be noticeable draining battery, in short term. Even if fuel pump on, which it should not be.

Second any aftermarket wiring done or toys added.

Third electronic (relays & controllers like ECU). Fuel pump should not be running with key just in IG or turned turned to on. Unless engine cranking or running. So the fuel pump circuit is where I'd start after above confirmed working as should.

 

[CLEM3]

Look at/for VIN # BK 2 head, center, just below head cover. Missing would be clue a replacement engine. But the wire harness looks 100 series, which would have to be. There are a number of signs I look for, showing sloppy engine swap. I can't see those in picture.

BTW: I see what looks like coolant leak at rear water bypass joint pipe to heater Tee. The pipe if to much side to side pressure on it, will leak at base where pressed in. This happens during heater Tee & hose replacement. It may just be coolant spill and not cleaned during heater Tee service, I can't tell from picture.

In a 2002 LC it is very limited what gets power, with key just in. You should see security light (center dash console) go off as key inserted. Which confirms you've a master key and working immobilizer system. But this should not be enough, to drain battery over short period. Even if fuel pump getting continuous power, which should it not be.

First, I'd be taking a look at battery condition, it's post & clamps and alternator as first step. As you should not be noticeable draining battery, in short term. Even if fuel pump on, which it should not be.

Second any aftermarket wiring done or toys added.

Third electronic (relays & controllers like ECU). Fuel pump should not be running with key just in IG or turned turned to on. Unless engine cranking or running. So the fuel pump circuit is where I'd start after above confirmed working as should.

Thank you for all the suggestions. I’ll run through the list later day. I sealed up the water pipe leak while doing the knock sensors. Here are some other pictures while at wait for my oil change.

 

[2001LC]

NP

With those pictures I see a number of issues, likely from poor install of engine. A strange one, is wire harness block on/over BK1. Not sure what to make of it.
BK2 VIN plate missing and additional wire routing issues.

I'd run through, FSM fuel pump control circuit test.