My Taco Possessed? Weird Electrical PROBLEM.

My 2007 is acting like it's possessed. Replaced the ignition coils and plugs, and when I reconnected the positive battery cable the engine started WITHOUT THE KEY INSERTED. Scared the hell out of me.

As usual, I disconnected the positive battery cable before starting the job. To save my computer settings, before starting the job I connected an OBDII Vehicle ECU Emergency Power Supply Cable Car Memory Saver (3Meter) from the Taco OBD port to my car's aux power receptacle. First time I've tried this device, recommended by Scotty Kilmer on Youtube.

Coils & plugs were easier than I'd expected. All went well until I reconnected the battery positive cable, at which point the engine instantly started up with the ignition key in my pocket. The engine ran normally, just as if I'd started it with the key.

• Disconnected the battery cable: engine continued to run (OBD cable still connected to my car). Reconnected battery cable.
  
• Disconnected the OBD cable.
  
• Inserted the ignition key.
  
• Turned to the "aux" position: no change.
  
• Turned to the "start" position: no change except the starter attempted to engaged with the engine running, giving the usual grinding sound when this bonehead move is attempted.
• Turned key to "off:" no change.
• Turned key to "start" again for about one second: starter attempted engagement, which shut the engine off this time. Not too good for the starter tho, so turned key back to "off."

OK, so at least now the truck didn't have to run until the full gas tank was empty.

Hoping the problem was fixed, with engine off, turned key to "start" and the engine started as normal. Turned key "off" but the engine continued to run, ignoring the key position. Went through same steps above, with same results: only way to turn engine off was to turn key to "start," letting starter attempt to engage, which shut engine off (still not too good for starter).

At that point I stopped, closed the hood and started a net search to see if a solution is available. No joy.

I don't know what happened, let alone how to fix this. Suggestions?

TIA

 

What engine?
Does your truck have the immobilizer?
See pic below for what to look for.
The security light should flash with the key out of the Ignition.


Remote start?



Something is wrong. Really wrong.
It would suck to wake up to a truck that’s run itself out of gas.

 

First off: Do not Google "What happens at the end of Christine."

 

There's gotta be a remote start system involved here or some seriously fried wiring, there's no way for a 2nd gen Tacoma to start by itself as wired from the factory without some serious electrical shorting going on.

 

Yeah - I refuse to install any start/alarm system anymore that requires splicing/tapping. Luckily now days there are a lot of them that plug directly into the system. ALL the ones I've ever had/tried/known that splice or tap into the wiring ALWAYS have problems of some kind after a few years for various reasons, usually corrosion at the splice/tap.

 

4.0L V6, 4x4 5-speed Automatic, 5.0 ft. Bed, crew cab.

Does have immobilizer, and it's flashing red with engine off.

Pretty sure it has a remote starting system; I bought it used six years ago and it has a device labeled Directed HX Plus on a 3-wire cable mounted above the driver's sun visor. The seller gave me the keys, a key fob (which I've never used nor programmed), and two small black remotes. One is labeled "Avital" and has a single button, the other is unlabeled with no button (I can't remember for sure whether this second device came with the truck or is for something else).

Since I never used either remote, I changed the batteries in both; neither would shut the truck off, or do anything at all I can detect.

 

Short internet search reveals "Directed HX Plus" unit is just an antenna, which I assume sends a signal to some sort of remote restart system. If this is correct, where should I look to find the actual remote start system and how do I disable it?

 

I don’t know how the truck started with no key in the ignition, if it has the immobilizer?

That isn’t good.

 

Remote start/alarm systems are typically tied in under the dash near the steering column.
The best way to remove them is find all the wiring that isn't factory, take all the taps out of the wires they tapped into, repair any wires they cut and/or spliced into, remove and throw the rat nest of wire you will likely have into the trash.

 

Remote Starts typically have a bypass for the immobilizer whether it be an extra key chip stuck somewhere or a hardware bypass.

 

Would the immobilizer light be flashing even if a remote start bypass is installed?

 

Not sure, the only dealings I have with aftermarket remote starts is removing them when they cause issues but my hunch would say yes when the system isn't active it would be.

 

Check the electrical portion of the ignition switch, might have contacts fried and touching when they shouldn't

 

Yes. My Viper alarm does. Your hood pin switch is seized or disconnected. Usually up on the rad support. Basic plunger style switch. If it’s out, and you saved settings as you said, the remote start probably saw a “trigger” event and fired up. Pressing the brake pedal “should” kill it, if it’s wired right.

*edit* Your key on then off sequence was most likely the manual override if the brake switch doesn’t work.

 

I have no idea.
But I’m curious how they bypass it.
AFAIK, when the light flashes it kills signal to the injectors.

@Dm93 experimented with the system once. But that’s a different subject entirely.


My advice is, figure out if you have a remote start system. And if you do. Remove it.

 

@destin_meeks Calling the cavalry.

 

Yup, my 2 cents the ignition switch is buggered.

 

I have a feeling some bugger caused it to be buggered. The chances of the ignition switch and the anti-theft system both being bad is slim. I mean there needs to be a transponder chipped key CLOSE to the ignition even for it to start.

Something is wrong. My bet, it’s due to someone else doing something previously.

 

Can't start getting into the guts of the problem until tomorrow. Will post what I find.

I was standing at the left front of the engine compartment when I reconnected the battery cable, so the key was about 4' from whatever sensor is inside the dash or column. The thing that concerns me about proximity is that even if a correct signal was received, the ignition switch was not activated and the engine started instantly when I connected the cable. This seems to me to signal it's something other than something related to the key/in-dash sensor connection.

 

I agree. There is something else at play other than the proximity of the key.

It will interesting to see what you find.