2007 G6 the traction control light service light came on how do you fix it?

these links can assist you the C0242 code is set due to the P2135 code the C0242 is set due to the computer not being able to perfomr traction control due to the P2135 code
repairing the P2135 code will correct the C0242 code
the P2135 is saying the computer sees the 2 throttle position sensors built into the throttle body do not match
this is usually cause by one of 2 things
1 ) the connection at the throttle body or possible terminal crimps inside the connector have bad connections
2 ) the throttle body itself has an internal failure
the best action to take is to pick up a tube of dielectric grease sold at most local auto parts stores and disconnect the connector at the throttle body and pack the connector with the grease then plug it back in and clear the codes and see if the problem goes away
if the problem comes back replace the throttle body connector sold at most dealers and shrink wrap in the new connector to the existing wires one at a time
if the problem still does not go away then replace the throttle body https://www.yourmechanic.com/article/p2135-obd-ii-trouble-code-throttle-pedal-position-sensor-switch-a-b-voltage-correlation-by-blake-griffin https://www.engine-codes.com/c0242.html

No , reduced engine power message is most often caused by a problem with electronic throttle control , your best bet would be to take your vehicle to a qualified repair shop.

With a scanner retrieve engine faulty code.
The faulty codes will tell you what to do.

Hope it helps.

Reduced engine power on GM vehicles has to do with the electronic throttle control .( Electronics ) Your best bet is to take your vehicle to a qualified repair shop or a GM dealer ! GM Reduced Engine Power Mystery Solved 04 Silverado REDUCED ENGINE POWER Case Study Part 1

maybe you have water in the electrical connector for your traction control

when you have the fault codes read to find the exact sensor failure or cause , have it fixed then reset the ecm as the ecm will reduce the performance(limp mode) for safety reasons

how do you fix the "reduced engine power" light on the dash bard of a 07 Chevy Impala LTZ and "Service Traction Control"?

you may have a bad mass air flow sensor. engine goes into protection mode when this happens so it doesnt damage the engine. or your throttle position sensor is failing as well. best thing to do is check and seeif you have a check engine light on and have the code read.

It sounds like these things are all related. When the a computer sees a problem in the Electronic throttle system, it will dissable traction control, and give the reduced engine power alert because the powertrain computer does not know the value of throttle postion.
Codes will need to be scanned in the computersto begin diagnosis.
TechJK