"Check hybrid system" failure & P0A0F code

You need three things to have an engine run: 1) air (flow into the engine, and exhaust out) 2)fuel (of good quality and correct quantity delivered to each cylinder) and 3)heat (both proper compression as well as spark at the correct time.

Have you tested fuel pressure- how many psi? Does Techstream show a RPM signal, a MAF sensor reading, and fuel injector pulse when you attempt to start the engine? Does the injector actually deliver fuel if/when triggered? Does any of the coils produce spark? What is engine compression?

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The Repair Manual says the detection condition for DTC P0A0F-205 is “Abnormal signal input from ECM (engine is unable to start),” and the inspection procedure is to check for engine DTCs and troubleshoot those. If there aren’t any engine DTCs, Toyota says to replace the engine control module (ECM).

I’m not sure I’d do that immediately: the Repair Manual authors assumed you’d be using a Toyota diagnostic system that would find any DTCs stored in the ECM. If your Techstream system uses an inexpensive vehicle interface module, not one tested by Toyota, an incompatibility wouldn’t be out of the question. That’s why I asked if you could see the Data List for the ECM (in the Techstream software, under Powertrain > Engine and ECT > Data List), which would prove that your computer can talk to the ECM.

If the throttle position sensor is suspect, have you done the Active Tests for the throttle? The Repair Manual for model year 2007 (RM03Q0U) lists these as “ETCS OPEN/CLOSE SLOW” and “ETCS OPEN/CLOSE FAST,” the names you’d see on Toyota’s older hand-held Intelligent Tester. (ETCS is electronic throttle control system, by the way.)

If you have a Techstream system but aren’t an experienced user, you may find it convenient to refer also to the Repair Manual for model year 2008 (RM07X0U), which gives directions for Techstream, such as the new names for the tests, “Control the ETCS Open/Close Slow Speed” and “Control the ETCS Open/Close Fast Speed,” as listed in the Techstream software under Powertrain > Engine and ECT > Active Test.

 

Thank you Electroingenieur,

I think I am on the right path at this point. According to the most recent code ( along with PA0AF) is the code P2112 which means that the throttle body plate is stuck in the closed position... presumably by either the malfunction of the motor which operates it OR the TPS. Is the TPS cleanable or should I just replace it? What goes bad on these parts, in your experience? Thanks for your help! IT is timely and definitely getting me closer to getting this car running again. The odd thing is that once I took out the throttle body and made sure the connections were good and all, the thing ran fine for about 10 minutes. Then the same code was displayed and the car went into safe mode... Perhaps the TPS works intermittently? Does the new/used TPS have to be reprogrammed and do I find that in TS utilities?

And you are right, I am not such a sophisticated TS user... I can go to active mode and read numbers however. Learning bit by bit.

 

In Toyota’s servicing strategy, the entire throttle body (throttle with motor body assembly, part number 22030-21020) is replaced as a unit. You can try to clean it, but there are no published procedures to replace parts of the assembly or make adjustments.

 

I dont see how op had it run when he sprayed down the intake if the tb is stuck closed

fuel pressure, injector pulse

if you feed it fuel and it goes, its not getting fuel!

if you try to hold the tb plate open, and the motor works.. it will immediately close when you ready the car

 

What about a whole assbly from a junk yard? Is there a need to run utilities to reset it?

 

The quality of a used part is unknown, of course—but if it passes the appearance, throttle control motor resistance, and throttle position sensor resistance checks in the Repair Manual inspection procedure, and the price is right, it could be worth a try. The gasket, part number 22271-21030, is shown as non-reusable, however.

There’s not an initialization or learning procedure for the throttle body, as such. The Repair Manual installation procedure mentions only the need to initialize the power window regulator, as might have to be done anytime the auxiliary (12-volt) battery is disconnected.

 

before you go to the effort of replacing it why not see if it returns to closed position when you hold it open while you ready the car, be careful of fingers use a screwdriver or something they close with decent force

 

Car will NOT go into READY mode... when trying to start engine after clearing codes with TS. It immediately throws code P0A0F along with with either P2112 or P2111. Before the red triangle appears, there is always a check engine light on first... I have tried 3, yes 3, different throttle bodies with motor and TPS intact. I replaced all the spark plugs and coil packs because i was also getting misfire codes... I removed and cleaned the injectors and installed new O rings, etc. The only advice from AllData that I have at this point is to change the ECM... I am not sure WHICH ECM they are talking about but I am not getting any closer to a solution. I am hopeful that SOMEONE has some experience about this problem? Can you point me in the direction of where to find resistance info on the motor and TPS?
Thank YOU!

 

The sections in the repair manual for P2111 and P2112 have some of that info for the motor (and a reference to the section for P2102, which has more). The section for P0120 has a bunch of information about checking out the position sensor.

There are many ECUs in the car, but only one of them is the ECM.

 

Is it the one to the far RIGHT of the passenger side under glove box?

 

Got it running today. Removed and replaced the 12V battery, which was marginal. Now the car will go into READY mode and the engine will oscillate between high rpm's and low rpm's before shutting down. NO CODES....

 

Getting code P0121 now along with the P0A0F and no start. We have put in 3 different throttle bodies with 3 different TPS so unlikely the issue is the TPS. Any ideas on how to proceed from here! Thanks.

 

Any updates ? I have similar codes.

 

Having the p0a0f and p2111 code at the same time. Is your car fixed by now? Thanks