Also posted this in Tech section 1-4 slow down light sometimes stays on when the ignition is on,and stays on when the engine is started,5-8 goes out. Doesn't do it all the time. Also pulled the ECU covers to check the codes,where is the button.There is a a plug with 3 wires next to each ECU which has a cover on it. Car is a 94 348GTS
The Cat ECU could have a crack on it letting moisture in it. Swap the Cat ECU's from side to side & see if the lights reverse. If so replace the bad Cat ECU. They are in the engine compartment on the back side of the plate with the coil on it. 2 nuts they come right off & unplug the 2 connectors. Easy to identify. Did mine last weekend. Good Luck, Chris
Swapped the round earlier and the 5/8 light stays on,so I guess it's a new ECU. Strange thing is you can start the car with the light on without power loss.
