1999 lx470 crank no start

[DIRTBIKEUSA]

Kinda stumped helping out a local college kid that’s been driving grandmas old lx470.
Truck has 250k miles. Not in the greatest of shape. Truck has much deferred maintenance.

Kid says it’s been having issues starting. Engine cranks fine. Checked all fuses under hood and dash. High amp Box fuses off battery +pos look good. But did not remove them. Checked and cleaned battery terminals. Battery is low charge from so many cranks so I did used cables later on and it cranked strong while hooked up to my tundra.

No fuel supply at under hood fuel filter. The young man already swapped the fuel pump. I checked his work and it looked good. But no fuel pump action when cranking. I did remove the supply line at pump and some fuel came out so the pump spun at some point.

Another issue is no spark. Truck has individual coils so I checked just #1 driver side.

Lx470 had RAT DAMAGED wires, see pictures. I repaired all the chewed wires and tried starting and the check engine light came on just one time with key on engine off. But now check engine light does not come on.

One more thing my scan tool is not reading the OBDII port. BlueDriver says no vehicle connected..

Thinking crank sensor now. What do you all think? Maybe Immobilizer? Maybe combo of issues? Kinda stumped.

I will try to answer any other questions about my diagnosis that I missed.

Thanks!

 

[kevgentile]

Good place to start.

My immobilizer fix

I got the famous crank but not start immobilizer problem. I replaced the 20A EFI fuse with a 30A fuse and it started right away. However, it was a temporary fix. I had the same problem again 4 days later. This is what I did to get the engine started. It has been working with no problem for...

forum.ih8mud.com

 

[DIRTBIKEUSA]

Good place to start.

My immobilizer fix

I got the famous crank but not start immobilizer problem. I replaced the 20A EFI fuse with a 30A fuse and it started right away. However, it was a temporary fix. I had the same problem again 4 days later. This is what I did to get the engine started. It has been working with no problem for...

forum.ih8mud.com

Thanks!!!

 

[DIRTBIKEUSA]

Well, I did the immobilizer bypass and still no start. Seems like the fuel pump ran for some time becuse I had fuel up to the filter but not out. Sent the kid to get a replacement filter. Like I said this truck has A LOT of deferred maintenance in addition to rat damage. I’m not sure what else to do at this point other that crank sensor and fuel filter. I’m waiting for the kid to get back with fuel filter so I can do a spark check. I look a little foolish at this point..

 

[medtro]

Reset hidden cut off switch?

 

[DIRTBIKEUSA]

Reset hidden cut off switch?

I have not. Can you point me to that?

 

[kevgentile]

I have not. Can you point me to that?

Yellow switch on the driver's right side foot well, behind the center consoles side panel.

Are you able to communicate with the obd2 port now?

 

[DIRTBIKEUSA]

Yellow switch on the driver's right side foot well, behind the center consoles side panel.

Are you able to communicate with the obd2 port now?

Thanks! I will have to try tomorrow. The kids truck is park at his place. Will update when I get out tomorrow.

 

[DIRTBIKEUSA]

I’m at the kids lx now. The last relay I used for the bypass has a loose pin so I’m trying another. So I’m live at the lx now if anyone wants to chime in..

One he get here I will try the reset as well.

 

[medtro]

Do you have blinking immobilizer security light when it cranks with no start?

 

[LandCruisinMy93]

I assume you have checked for the security light. That it is on when entering the vehicle and that it goes off when the key is inserted in the ignition?

If that functions as it should then I would check the fusible link assembly coming off the battery positive. If that is all intact you need to check the ECU is receiving power.

If that checks out, then check that the fuel pump receives initial power upon turning the key to the run position. If the fuel pump isn't turning on it could be part of the mass air circuit or a blown fuse somewhere. That specific rodent damage location is pretty common. I would google search for the other common rodent damage locations in the engine bay as there are a few. For whatever reason that tends to be the most common location.

 

[DIRTBIKEUSA]

Do you have blinking immobilizer security light when it cranks with no start?

Will check …

 

[DIRTBIKEUSA]

I assume you have checked for the security light. That it is on when entering the vehicle and that it goes off when the key is inserted in the ignition?

If that functions as it should then I would check the fusible link assembly coming off the battery positive. If that is all intact you need to check the ECU is receiving power.

If that checks out, then check that the fuel pump receives initial power upon turning the key to the run position. If the fuel pump isn't turning on it could be part of the mass air circuit or a blown fuse somewhere. That specific rodent damage location is pretty common. I would google search for the other common rodent damage locations in the engine bay as there are a few. For whatever reason that tends to be the most common location.

Pump does build “some pressure” as I have checked back at the pump out put tank connection and it back flows out.

Will check security light.

Fuses off bat look good. Is there another link in addition to the picture shown?

I checked all relays and fuses and all have power to them in the fuse boxes. Swapped some relays for spares I had and no dice..

Will update soon..

 

[DIRTBIKEUSA]

Pics

 

[DIRTBIKEUSA]

Update. No security light. Dead dash until KOEO. No CEL still.

 

[DIRTBIKEUSA]

I’m going to come home now.

 

[DIRTBIKEUSA]

Beginning to think this truck went brick cause someone tried to steal it…

 

[DIRTBIKEUSA]

Or his copy key keeps resetting the computer cause the chip is blank. Oh well. Dealership time..or

Maybe original key will reset and start OBD scanner can reset after I get computer to read and start.

 

[medtro]

Lx470 had RAT DAMAGED wires, see pictures. I repaired all the chewed wires and tried starting and the check engine light came on just one time with key on engine off. But now check engine light does not come on.

It has no chance to start without a check engine light with key on engine off. May be double check those wires again?

 

[medtro]

Update. No security light. Dead dash until KOEO. No CEL still.

No security light with key inserted or not inserted?