2009 Toyota Yaris no communications after throttle body clean

Hey guys. so we ran into a problem with our 09 yaris. The engine was running a bit poorly and we noticed the spark plugs were way out of gap (.066-.070) instead of the .044) We also cleaned out the throttle body since it was gunged up pretty bad. We got everything back together and now the car will not start. There are no dash lights when turning the key on and absolutely no activity when trying to turn it over. no clicking, no noise nothing. We checked the battery Voltage and saw 12.8 V. Wenoticed when we cleaned the battery terminals and reconnected that there was absolutely no spark when attaching both terminals. Most of the accesories seem to work (hazard lights, horn, radio, blower motor) but I’m really not sure what happened during that time.

Check for the a good ground for the battery. Also check the 12v side of the battery cable. Trace it to the connection point away from the battery. Is there 12v there? Same for the ground? You need both and I’d bet one has failed.

So I ran a ground test. I hooked the negative battery post to the body ground, the chassi and the engine and got about 12.46V from what that sounds like, acceptable voltage drop. I have one of the basic scan tools that reads diagnostic codes. when the key was on and we attempted to scan we kept getting a fail.

I ran avoltage check across the positive post of the battery and it’s connector away from the battery (if i misunderstood your instructions on that I apologize) and got nothing at all. 0 V. I ran a check between both positive and negative battery cables while disconnected from the battery and got .08V

With the voltmeter’s black probe on the negative battery post and the red probe to the end of the red battery cable away from the battery is 0 volts? If that is what you did, then the cable or clamp is bad.

yup that unfortunately is what I’m getting. what i don’t get is why most of my accesories still work. should the ngative battery cable be hooked up when i do this test? I know the positive shouldn’t but i din’t know if the negative should be hooked up.

No. Not if you tested as I described. If your accessories still work there must be an additional connection to the positive battery terminal. Likely a smaller wire coming off the battery clamp. If there isn’t one of those, you did not do the test correctly. There can’t be any accessories working if both cables from the battery are not connected somehow.

There do appear to be 2 larger wires running into the clamp. I tested the main terminal that hooks onto the battery and the 2 larger gauge wires with the negative post. all 0’d. if i hook up the battery fully, the accesories work.

Ifi hook just the positive battery terminal up and check from negative post to any of those connections on the positive side. i get 12.6 all around. one of my friend’s mentioned a potential security lockout that may have happened. at this point i’m clueless. There don’t appear to be any blown fuses.

I would expect 0 volts with that test in the picture, you’re not testing anything in that picture.

To me, that indicates one of your main power fuses has blown, probably the main one to the alternator.

I wasn’t sure the test i was described made a ton of sense. again it could be me misunderstanding the instructions and if so I’m sorry. I gave a glance at the 60 and 120A fuses on the positive area and they looked good.

I am beginning to think that you and whoever makes up the we part of this crew might need to back off of some of these repairs . You certainly seem to have the one step forward and two steps backward going.

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yeah we’re not perfect. We’re trying to do our best doing DIY because we can’t afford to take our vehicles to the mechanic like some people can. Yeha it doesn’t always work and things go wrong. it’s how you learn. I try to watch some of the more popular car repair channels online as much as I can to help me learn what I’m doing. (ETCG, SMA, ChrisFix) You’re doing absolutely nothing to contribute to this thread to help us work on our problem. I don’t know what your personal grudge against me is but I’ve really had enough and would appreciate you staying off my threads.

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No, what he was saying is to put negative test lead on negative battery terminal, then put the positive test lead on other end of the positive cable, not the battery side, but where it connects to the starter. You should be getting 12 volts there. (Both battery cables need to be attached to battery for this to work). If that is good do the same test, except for the negative cable.

Did you try jumping it by any chance? I have seen cars with headlights on that dont make a noise when key is turned (battery too dead to crank, strong enough for lights). I’m kind of leery of that battery that says 90 day warranty. Thats super short in the battery universe. When all these other repairs were going on, was the key on and were you listening to radio (with engine obviously not running?)

i’ll definitely give that a try Thanks!

We did not try jumping it. I suppose we could’ve run a voltage drop on the battery wehn attempting to crank it. I could also run down to my local advance (5 min from me) and have them test it. The battery was purchased from them back in October last year. We did not have the key on when doing repairs but we did (and I’ll admit this was our dumber move) leave the battery connected while doing this. I definitely told my friend that anytime we do any car work from now on, that negative terminal gets disconnected. Obviously any potential damage has already been done. But hey, you tend to learn from that mistake pretty quickly if you short your whole car out. Thanks for clarifying the test that needs run and I’ll report back later after work to see what we got.

Stealing a line from someone else

swap it or test it, “looks GOOD” is for the ladies NOT fuses

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I doubt leaving the battery connected hurt you too much. Try jumping it.

Tried jumping no change :confused:

I did the test both positive terminal on the battery and the ground of the starter and the negative terminal to the positive end of the starter and got 12.5V. I disconnected the solenoid wire (single purple wire) and connected it to the negative terminal of the battery and attempted cranking and got nothing. From what Ican gather that tells me either a relay is blown or given I don’t have dash lights to begin with. The computer isn’t sending the starter signal. I did get the wiring diagrams with the subscription I got to alldata DIY. certainly helpes to translate the spaghetti.

So right now, when you turn the key to on, you have no dash warning lights? No lights come on?