Truck wont fully start.

I was wiring a microphone from my head unit to the a-pillar yesterday and after doing so my truck won't fully start. It cranks for a second at most then dies down. I have a 2009 Tacoma.

It can't be a coincidence that this happened at the same time I was wiring my microphone so I feel like it has to be something I might have done (i.e. unplugging something by accident when wiring the microphone)

Things to note: When I first noticed the car wasn't starting all the way when turning the key, I tried it with my remote start fob and it worked (It's an after-market Viper Alarm & Remote Start kit). When I tried this again today when going back out to try and fix it, it no longer worked.

Something I just learned: If I hold the key turned in the start position when turning it, the truck fully starts (though the engine sounds weird; I assume it's because the starter/ignition is still engaged because the key is being held to the start position).



Any bits of help is appreciated, thank you.

 

Try removing your mod.

 

Have you made sure the battery is connections are clean and tight? a loose positive or negative will mess up the start.

 

did you have the battery disconnected ?
When you pop the terminals off , the truck re-sets to factory throttle specs . It takes 30 minutes for the computer in your truck to re-adjust to a dirty throttle body
Maybe clean your throttle body and try again

 

Yes I have, I've also disconnected the battery for 5 minutes or so and reconnected it.

 

Check all fuses with something like this:

 

At first this is what I was thinking however, the remote start is no longer working and, when I turn and hold the key in the start position it starts and runs but when I let it go it turns back off. I'm thinking it could maybe a bad ignition switch?

 

I didn't have the terminal disconnected, do you think this could still be worth trying?

 

Pro tip: Disconnect the battery before attempting any electrical mods on a Tacoma.

 

The thing is I didn't even do any modifications, the microphone had the wrong size jack so I wasn't even able to hook it up. However, I did have to take out the center ac controls and clock so maybe that could of done it? At first I was thinking it had something to do with the immobilizer but when the vehicle was able to start by being held in the on position I thought otherwise.

 

No to the bad ignition switch. Just what did you do to incur a no start condition? Running a wire for a microphone from the head unit to the Pillar should not cause the problem. If your no start problem is strictly related to your wiring job I would think about anything you could have done. Did you tie into a power source? Did you blow a fuse? Did you see a spark on a wire?

When you say that it cranks for a second and dies down that tells me that the computer will not allow the engine to run. So what did you do to not allow the computer to run the engine? How close were you working to the ECM?

Edited: After reading your latest post You might have blown an inline fuse to the ECM. There are probably two sources of power going to the computer and one of those sources is probably the ignition start switch when engaging in start.
It can also be unrelated to the recent work that you have performed.

 

If I understand your question correctly then no, I didn't tie into any power source. I suppose checking the fuses would be a good idea so I'll do that next.

To be honest with you I'm not exactly sure where the ECM is so I couldn't tell you.. when I was browsing YouTube and other threads I came across an ECM reset procedure as a possible fix (involves using a paper clip on the connector pins) but I didn't feel comfortable trying that just yet. If the connector is right next to the ECM then I'd say it's possible that I could of hit it when wiring the cable. I used fish tape to bring the wire through the back of the steering column so it's possible I could have hit it.

And lastly, I didn't see any sparks on any wire.

P.s. may I ask why it wouldn't be the ignition switch? I'm reading the symptoms of a bad ignition switch online and one of them says that it will start and then die immediately after. It still seems unlikely to me just because it happened right after I finished wiring the microphone cable but I guess coincidences are possible, I just want to be sure.

Thanks

 

Hey I'm just now reading your edit, you might be right about that. I'm assuming this would be one of the fuses that's under the steering wheel inside the truck, do you have any idea which one it might be? I looked at a fuse diagram online and don't see any labeled ECM

 

Bump

 

Tried it again with the remote start and it worked. Dash lights and mileage not showing when key is in on position

 

Maybe a little video uploaded to utube to help us help you .
I agree with your ignition switch theory but you need a test light to check the wiring and fuses to the ignition switch before you replace the actual switch
They call this hot in crank and hot in run . This means 12 volts are being supplied to the cranking circuit and 12 volts also need to be supplied to the ignition run circuit .
There are 2 different voltage circuits feeding the ignition switch . Judging from your description of the problem , my first guess is a blown fuse within the ignition circuit or a broken wire
These are going to be large fuses under the hood of the truck and the remote start you have also uses these circuits .
Aftermarket remote starts can be real fun to work on . I hope you have the installation instructions for the remote start . All it would take is to accidently brake one of these crimped connections under the dash and you are in for a world of grief

 

His old man here. I have checked voltage on the 3 ignition fuses (plus all others ) by the kick panel.
IGN 15A has 12vdc when cranking.
IG1 No. 2 10 has 12vdc.
IG1 10A has 12vdc.

When using the aftermarket

$55 Directed DB3 All-in-One Door Lock & Override Module, Black

Directed DB3 remote smart the truck starts and runs and the dash ACC lights are on.
When using the key it will start and die immediately. If the key is held in the starting position the truck will run.
As soon as you release the key the truck dies.
When you turn the key to ACC no dash lights are present.
To me this would point to an issue with the aftermarket remote start not sending 12vdc to the ignition run circuit.
I am going to check the wiring diagram and see if I can pinpoint which circuit on the DB3 sends dc to the ignition.
Replacing the ignition switch didn't fix the problem.

 

Thanks Larry .
Is the boys Tacoma a 4 liter engine or 4 cylinder ?

 

4.0 V6

 

Under hood fuses and relays got power ?
https://www.carfusebox.com/toyota-tacoma-2009-engine-fuse-boxblock-circuit-breaker-diagram/