Is your electronic throttle control indicator on?
The accelerator pedal has evolved from a mechanical connection to the carburetor to a computer-controlled electronic throttle controller. Pressing the pedal sends a signal to the engine to go faster – an important function. In modern cars, an electronic throttle control system handles this task, monitored by sensors.
Warning lights like the electronic throttle control indicator light can alert you to a problem before it gets you stranded. Let’s take a look at how this system works, what causes the throttle light to come on, and whether it’s safe to continue driving.
What is the Throttle Control Warning Light?
The Throttle Control Warning Light is located on your car’s instrument panel. It comes on when it detects a decrease in electronic throttle control performance.
Like the Check Engine Light (CEL), Traction Control light, or other warning lights, this light indicates a problem that may require corrective action. Consult your vehicle’s owner’s manual for more information.
If the TCL is constantly illuminated or flashing, the on-board diagnostic system (OBD2) has set one or more trouble codes. With a diagnostic tool, you or a service technician can view these codes and use them to find faults in your vehicle’s fuel-air delivery and related systems.
What does the Electronic Throttle Control light look like?
The TCL symbol on your dashboard looks like this: A short vertical flash between two vertical lines that bend inward. It’s usually yellow, red, or orange. This light comes on briefly when you start your engine to let you know that it’s running.
Note: Not all cars have a throttle warning light. Check to see if your car came with an owner’s manual (printed or online).
If so, your owner’s manual will also tell you where this light is and what it looks like. Newer models of Dodge, Chrysler and Jeep have this feature.
What causes the TCL to light up?The throttle control light will come on if any of the following faults occur:
1) Electrical trouble with the ETC system
Loss or interruption of the signal between the ECU or the accelerator pedal module.
Possible causes
– Faulty wiring or loose/corrosive connections
– Pedal module failure
– Mechanical error in the module connection to the accelerator pedal
2) ACV butterfly valve inhibited operation
Valve cannot move smoothly from idle to fully open position
Possible causes
– Dirt or corrosion around the butterfly valve and/or shaft
– Mechanical failure of the butterfly valve
– Water ingress into the ACV causing internal corrosion and servo failure.
3) Sensor failure
The electronic throttle indicator light may come on if any error or failure occurs in a sensor such as the throttle position sensor (located in the air control door).
Symptoms of an Electronic Throttle Control Problem
Any failures listed above can affect the operation of your engine. Possible malfunctions include problematic behavior such as:
– Engine stalling
– Engine misfire
– Rough or uneven idling
– Inability to accelerate smoothly
– Inability to maintain a constant speed
– Slowing down of travel
– Car does not speed up once it has reached a certain speed.
– This can happen if the ECU detects that increasing speed would cause damage to the engine or related systems. This is called limp mode.
– Engine will not start or is hard to start
– Noticeable reduction in fuel consumption
– Black, smoky exhaust pipe
As mentioned above, when a problem occurs that causes the TCL to light up, an error code is generated. The Check Engine Light (CEL) will also be illuminated. ETC issues can sometimes be similar to other issues with the engine system, in which case OBD2 trouble codes can be extremely helpful in allowing for a proper diagnosis.