Engine died and all the lights

Towing my travel trailer up steep canyon road. 2wd, using S mode shifter to switch between 1st and 2nd gears to maintain speed etc. all of the sudden engine dies, 4hi 4lo and other lights come on. engine will crank but not restart. display says see dealership. Decided to disconnect battery in hopes things would reset. Disconnected for a few min and then reconnected. Truck started up and was able to make it the few more miles including off road to our camp. Suspect maybe something with the shifter? Any other thoughts?

 

What year? I believe there is a TSB on the fuel pump.

 

2017. had the fuel pump replaced about 2 years ago due to flex fuel hard starting and ethanol percentage. do you know the tsb number?

 

When you say steep and 1st&2nd, I begin to wonder if maybe your fuel is all being displaced toward the rear of the tank and simply starving the pump for fuel. How full is the tank? I also wonder if you might have a loose battery cable or ground somewhere and you were going so slow that the circuit stayed open for a longer time than it normally would under faster vibrations from normal driving. Been out in the wild for some time? Might have rodent damage to wiring occurring. Just my first thoughts. Good luck!

 

Being in 1st and 2nd jumped out to me too. I thought downshifting to 3rd was aggressive - he must be going around 25 MPH which begs the question - how big is the trailer?

 

Fuel tank is full. Filled up in town just prior to going up the canyon. Haven't been out in the wilderness recently until this trip. After disconnecting the battery and reconnecting truck seemed to run fine for the duration... Another few miles. The trailer is a 28 foot travel trailer.. Weighs about 7k loaded. The road has a couple really steep sections... About 15% grade....have to use 1st gear on those sections to make it up. I like to use the manual shifting a lot when towing as I can hold lower gears and use less throttle in most cases.

 

Perhaps you had a loose or dirty battery cable clamp and when you fiddled with it, it was tightened. Good luck!

 

My driveway is about 450' long at over 20% grade. I pull a 6K # trailer up it but I'm in 4L when I do it. Never a problem.

 

yes...we've done this climb in previous years without issue... something went awry this time.

 

I’d take a look for pending codes to get an idea what happened. When something like this happens, it will usually log as a pending trouble code in the ECU even if it doesn’t illuminate the CEL.

 

Going to run by a dealer to see if there are any pending codes.... If I make it home today... Fingers crossed.

 

Has there been any issue since getting it to start again after the battery disconnect?

Also, are you using the original OEM battery that came with the truck when new?

 

Please post up an update when you get it scanned. Quite curious. Hard to believe it is or was a battery issue since it was cranking. Sort of thinking there is a loose ground that ties into ignition, fuel supply, or cam/crank sensors.

 

No issues starting since disconnected battery. New battery installed about 1 year ago. Orig battery was still working but getting weak. Heading to dealer now to see about codes.

 

Dealer plugged in their scanner... No codes at all! So bizarre. Anxiously heading out on another trip tomorrow... Hopefully without issues.

 

My 2019 is not flex fuel, but isn't it a known issue that Toyota is not going to address? That the flex fuel trucks need to reset some adaptation that slowly drifts off over time? By disconnecting the battery you perhaps had it reset.

 

I monitor the ethanol percentage in an app all the time. Since the pump replacement it hasn't drifted off. The symptoms of that are different than this also.

 

Well folks, almost a month later and this has reared its ugly head again. Went to lake powell over the past few days...hot temps down there. approx 108-110. Made it down fine. next day during the heat went to a grocery store..left the wife in truck running. Came back out and all the lights and no start. re-set computer by disconnecting the battery and touching them together. started back up. drove to hotel without issue. once there and parking it went into limp mode (barely running, tach to zero, 4hi 4lo, traction light). turned off..no start. spent the next day deciding what to do. pulling boat off the water in the evening, went up ramp fine but when idling went into limp mode again. seemed to be heat related with idling. next day decided to try and drive it home...after driving around locally for a bit we headed out. 3 hours later all well...needed fuel. stopped to fill up and when stopped and idling limp mode again. had someone tow me into the shade, let it sit for a bit, reset the computer again. drove another 2 hours home....died at a stop light 1/2 mile from home....got a neighbor to tow me the rest of the way.
So...at the dealership they were able to reproduce thankfully...even with slightly cooler temps. after a couple hour diagnose...they determined that converting to the later model headlights, and tapping off the IGN circuit for the LED DRL is the culprit....they unplugged that and it "seems" to be working. not sure how its possible to be heat related, but i'm going to do some fiddling and see if I can say conclusively.

 

update: so I plugged the tap back into the ign fuse location and then pulled it out while the truck was running (i dont recommend doing this) symptoms were the same as i've been having. so I think the fuse tap is loosing connection in the fuse box, maybe working its way up/out while driving. Still not sure how heat would have any effect other than maybe some expansion? going to run the truck for a while without it connected and just the normal fuse in there to see if the problem is resolved, then look into wiring the DRLs differently.