Skip the auto shop - Our mechanics make house calls

Q: What does the powertrain malfunction/reduced power (RTT) Warning Light mean?

asked by on

What does the powertrain malfunction/reduced power (RTT) Warning Light mean?

A: The Powertrain malfunction/reduced power is...

The Powertrain malfunction/reduced power is a warning that is illuminated when the vehicle is experiencing a condition - that if driven can cause damage to the engine, transmission or drivetrain. The warning is to let you know to decrease the load on the vehicle (typically speed) and is close to defaulting into a limp home mode for protection if it has one. Typically with this warning a code is set in one of the component located in the powertrain (engine control, transmission or traction control/ABS). It is possible that if it keeps occurring that it can activate another warning. If the problem resolves itself the warning may go away.

For example, if you have a heavy load, perhaps towing a trailer, and are going up a hill, and the transmission is starting to overheat. To avoid further damage the warning “Powertrain malfunction/reduced power” is illuminated to warn you to take steps like ease off the load to avoid overheating the transmission. If you decide to ignore this warning the vehicle may go into a limp home mode where the computers will cut back on the throttle and operate in a safe mode it knows is safe till the issue has been resolved, and the transmission temperature has cooled down.

Was this answer helpful?

Need advice from certified mechanic? Get help now!

Over 1000 mechanics are ready to answer your question.
The statements expressed above are only for informational purposes and should be independently verified. Please see our terms of service for more details

Ask a Mechanic
(100% Free)

Have a car question? Get free advice from our top-rated mechanics.

Ask A Mechanic
Over 10,000 questions answered!

Get an instant quote for your car

Our certified mechanics come to you ・Backed by 12-month, 12,000-mile guarantee・Save up to 30%

Get a quote

What others are asking

Q: Power windows stopped working.

Windows that don't go either up, down or both can be caused by several things. Problems with the switch, circuitry, window motor or regulator are common causes. A trained technician, such as one from YourMechanic, will be able to diagnose...

Q: Can I change my 4 wheel drive in my Jeep?

In order to to change the system, this will require major component changes like the transfer case and front axle assembly. The systems will need different controls along with different ABS programming if this can be done at all. The...

Q: Brakes don’t work, worried about a crash

Your vehicle is unsafe to drive in this condition and shouldn’t be driven until your problem is repaired. Being that you towed it to a shop, it appears from your question that they were unable to provide you with an...

Related articles

P0052 OBD-II Trouble Code: HO2S Heater Control Circuit High (Bank 2 Sensor 1)
P0052 code definition HO2S Heater Control Circuit High (Bank 2 Sensor 1) What the P0052 code means This code is seen when the Engine Control Module (ECM) tries to control the...
P0240 OBD-II Trouble Code: Turbocharger Boost Sensor B Circuit Range/Performance
P0240 code definition Turbocharger Boost Sensor B Circuit Range/Performance What the P0240 code means P0240 is an OBD-II generic code triggered when the Engine Control Module (ECM) detects the intake boost...
How to Avoid Back Pain in a Car
If you have back problems, sitting in a car for an extended period of time can be excruciating. Even without back problems, you could experience discomfort and soreness from...