Hey guys, I have 98 eclipse rs. My girlfriend switched the terminals around and now the battery light stays on. The fuse was blown. So I replaced it (under the hood). The light was still on. I changed out the battery and the alternator. The light is still on. I changed the ecu today and the light is still on. What would cause this? How would I diagnose this? Any information will be appreciated.

Well the cause is the battery connected backwards. And it's really hard to say why it's still on. You must have shorted somthing else tighed into that light. Go over all the fuses. How long was in connected wrong? You might have burnt up a wire somewhere!

It was on for about 2 seconds. I replaced the battery and alternator. I changed an Ecu with the same plug in. However, the light is still on. I know the alternator is not working correctly because the car dies. I am starting to think the voltage regulator is dead. Any ideas?

Anyone?

You probably fried the voltage reg!

I am trying to bypass the voltage reg via a external voltage regulator. I am following the exact instructions. However, the car is only putting outo 11.8 volts when running. Brand new battery and alternator

Anyone with a idea ton fixing this issue?

Anyone knows how to put a voltage regulator on a car?

what year is your car and what year did the replacement ecu come off of?

the 97 ecu has the same plug as the 98/99 ecu, but they have a few pins that are different.

98/99 ECU
PIN 8 (Blue) ---- To Generator Field Coil
PIN 39 (Blue) --- To Battery Light

97 ECU
PIN 4 (Blue) --- To Generator Field Coil
PIN 56 (Blue) --- To Battery Light