Electronic Throttle Contol(ler) for Dummies

[plarsen111]

Hi,

This morning I was driving to work in my 2000 Land Cruiser with 245,000 miles and I had no get up and go.

I pulled over, since I had no throttle, and saw that my dashboard was lit up like a Xmas tree.

In park, I hit the gas. Although my car was running, the engine would not rev up.

The shop believes it is the Electronic Throttle Controller. I have never heard of this (hence the "for Dummies" reference).

Apparently it is a $1400 part. Being a school teacher, I do not accept this, or I should say my checking account does not accept this.

Is there a part to be had for much less money? Is the diagnosis correct? Any other words of advice, such as definitely go used or new based on the part?

Your help is greatly appreciated,

Phil

 

[Mohammedqur]

Search Throttle Position Sensor (TPS) and APPS threads in this forum. Probably there's a cheaper solution for you in those discussions.

 

[plarsen111]

Mohammedqur, is that the same part with a different name?

Thanks,

Phil

 

[Sandroad]

Here are some excerpts from the '04 FSM. There are several parts to the electronic throttle controller and likely only one of them failed. Searches here might indicate the TPS or APPS as possible culprits. As a price reference, TOYODIY.com shows the OEM TPS as approximately $350. I didn't look up other prices, but it's easy to do if you know which part specifically is needed.

From the FSM:

"The Electric Throttle Control System (ETCS) is composed of a throttle motor that operates the throttle valve, a throttle position sensor that detects the opening angle of the throttle valve, an accelerator pedal position sensor that detects the accelerator pedal position, and the ECM that controls the ETCS system.

The ECM operates the throttle motor to position the throttle valve for proper response to driver inputs. The throttle position sensor, mounted on the throttle body, detects the opening angle of the throttle valve and provides this signal to the ECM so that the ECM can regulate the throttle motor.


This electrical throttle system does not use a throttle cable.

This accelerator pedal position sensor is a non-contact type.


The accelerator pedal position sensor is mounted in the accelerator pedal to detect the angle of the accelerator pedal. This sensor is electronically controlled and uses Hall-effect elements.


If the ETCS (Electronic Throttle Control System) has a malfunction, the ECM cuts off current to the throttle control motor. The throttle control valve returns to a predetermined opening angle (approximately 16°) by the force of the return spring. The ECM then adjusts the engine output by controlling the fuel infection (intermittent fuel-cut) and ignition timing in accordance with the accelerator pedal opening angle to enable the vehicle to continue at a minimum speed.

If the accelerator pedal is depressed firmly and slowly, the vehicle can be driven slowly.

If a ”pass” condition is detected and then the ignition switch is turned OFF, the fail-safe operation will stop and the system will return to normal condition."

 

[Sandroad]

Forgot to mention that this thread is in the forum FAQ:

https://forum.ih8mud.com/threads/tps-apps-problems.127474/

 

[TTO5]

Had the same thing a few years ago. Mine is a 2000 as well. I changed the accelerator position sensor on the side of the throttle body. Now at 245k. You probably don't need to change the throttle body

 

[AimCOtaco]

Here are some excerpts from the '04 FSM. There are several parts to the electronic throttle controller and likely only one of them failed. Searches here might indicate the TPS or APPS as possible culprits. As a price reference, TOYODIY.com shows the OEM TPS as approximately $350. I didn't look up other prices, but it's easy to do if you know which part specifically is needed.

From the FSM:

"The Electric Throttle Control System (ETCS) is composed of a throttle motor that operates the throttle valve, a throttle position sensor that detects the opening angle of the throttle valve, an accelerator pedal position sensor that detects the accelerator pedal position, and the ECM that controls the ETCS system.

The ECM operates the throttle motor to position the throttle valve for proper response to driver inputs. The throttle position sensor, mounted on the throttle body, detects the opening angle of the throttle valve and provides this signal to the ECM so that the ECM can regulate the throttle motor.


This electrical throttle system does not use a throttle cable.

This accelerator pedal position sensor is a non-contact type.


The accelerator pedal position sensor is mounted in the accelerator pedal to detect the angle of the accelerator pedal. This sensor is electronically controlled and uses Hall-effect elements.


If the ETCS (Electronic Throttle Control System) has a malfunction, the ECM cuts off current to the throttle control motor. The throttle control valve returns to a predetermined opening angle (approximately 16°) by the force of the return spring. The ECM then adjusts the engine output by controlling the fuel infection (intermittent fuel-cut) and ignition timing in accordance with the accelerator pedal opening angle to enable the vehicle to continue at a minimum speed.

If the accelerator pedal is depressed firmly and slowly, the vehicle can be driven slowly.

If a ”pass” condition is detected and then the ignition switch is turned OFF, the fail-safe operation will stop and the system will return to normal condition."

This is close but not the same for the 2000. The 2000 has both a throttle cable and an APPS but the APPS is on the throttle body, not in the accelerator. (the 04 FSM is easy to find online but not accurate in all regards to all models). IIRC I changed a TPS then the APPS, and finally the whole TB. In my case the gearing or motor were sticky so changing sensors had no effect.

 

[OregonLC]

For the 2000 you still have manual control in case of emergency. The last 1/3 or so of pedal travel manually operate the butterfly. It's difficult to modulate and you don't quite get WOT but it will get you off a trail or off the highway. The pedal feels like it hits a stop but it's just a secondary spring. Keep pushing and it will engage. I've completely unplugged TPMS and APPS to test and can drive around just fine. Don't know what year they went full electronic (2003?).

 

[RobRed]

Bottom line is the problem is a $300 part and less than 10 minutes with a philips screwdriver. Mine failed at 175000 miles.

 

[coldwiz]

This same thing happened to me on Tuesday morning. Once I turned the truck off and back on all was good except for the dash lights. I read the code and then cleared it and so far this hasn't happened again. My conclusion from researching this here on mud was to wait and see how problematic this becomes or doesn't become. Seems like for some people it is only an occasional occurrence that might happen once or twice a year. If that is the case, I'll probably just live with it. If it starts happening all the time, then I will go for the new APPS