4Agze Cel Comes On, But No Codes.

[B.L.Z.BUB]

I pretty much have a constant check engine light on my bigport 4AGZE yet whenever I do a diagnostic it comes up clear.

 

Car runs fine, no issues. I'm not sure if its in limp mode but I don't think so.

 

Any ideas?

[rian]

Did you try the ECU manual?

If you don't already have it here it is:

 

4AGE_ECU_Diagnosis.pdf

[B.L.Z.BUB]

Unfortunately nothing about having a CEL and no codes, plus GZE codes are different to GE ones.

[CorollaNut68]

You haven't been loving on it like you used to...It's gotten lonely and throws that light on so you'll touch it.

[ke70dave]

Perhaps give the ECU a reset (disconnect battery and jump on the brakes etc). see if it goes away?

 

or alternatively give it something to complain about (disconnect the TPS or map) and see what it does?

[B.L.Z.BUB]

I solved it by putting a switch inline on the power source :)

 

Battery was disconnected over the weekend installing the stereo. Might try unplugging some sensors. I have removed a lot of stuff like iscv, the iscv sensor, all the VSVs, basically all the unnecessary crap. It's probably trying and failing to trigger these, weird I get no codes though.

[rollamods]

if you don't have the constant battery feed wired correctly you will lose the codes when the ignition is switched off.

[B.L.Z.BUB]

I'll try this out and make sure I havent been turning the car totally off before checking as its only getting ACC 12v. Cheers! I wasnt aware it should get constant 12V.

[rian]

n00b.

[B.L.Z.BUB]

Haha, yup. My bad. I figured the ECU stored codes but it didnt even cross my mind it'd need constant 12v to do it. I thought it was magic.

[B.L.Z.BUB]

Actually I think my ECU doesnt have a constant 12V. This may be the issue.

 

EDIT: Yup, constant 12V to ECU is non-existant, not even getting switched 12V.

Edited November 12, 2014 by B.L.Z.BUB

[rian]

I don't understand. You mean there is no pin-out for constant 12V? Or it just hasn't been wired in?

[B.L.Z.BUB]

No constant to the 12V BATT pin.

 

Well I wired my loom up to the diagram specs but I'm guessing in the maze of wires there is a constant 12V that I have missed that feeds the ECU memory.

I wired a constant 12V from inside my dash to it but it wouldnt start and I smelled not good smell electrical. So I have run a constant 12V with an in line 10A fuse straight off the battery and it has now started. Without any weird smells.

 

As the GE ECU's are adaptive every time I have stopped the car everything it has learned has been wiped.

[B.L.Z.BUB]

OK sorted, getting a knock sensor code. Great, the hardest sensor on my car to get to.

[CorollaNut68]

Someday ...mechanics will evolve with that third arm we always end up needing.