Can emptying the brake reservoir set the check engine light???

[Ulysses]

I did two things. I replaced the coolant overflow tank. Should have been no problems there.

I emptied the brake reservoir and changed out the stock brake lines to stainless. Could that have been it?

It's going in for a check up, so i'll find out, but would like to know if that could have been the cause.

 

[Sean Roe]

I don't think anything older than the ABS cars of '01 have a reservoir fluid level sensor. Take a look at your master cylinder reservoir to see if there are wires to a sensor.
The only things that should set the light that I know of for sure are the parking brake switch (at the hanle) and the switch on the combination safety/proportioning valve. It's possible that when you were bleeding the brakes the internal rod moved and closed the circuit for the warning light. It would do this if there were too little pressure on one end, front versus rear (designed to close off the low pressure end in case of a brake failure and turn on the light to let you know there's a problem).

 

[Ulysses]

But wouldn't that only trip the brake warning light?

Thanks,

Ulysses

 

[Sean Roe]

My mistake, I thought you meant brake light. Answer is no, those items will not cause a check engine light.

 

[Rich Carlson]

You said that you replaced "coolant overflow bottle". Please clarify..... The coolant overflow bottle is behind the front facia. The pressure coolant bottle is under the hood next to the right head. Which was it ??? This may help. BTW, the only way to turn on the MIL, is to disconnect something that the PCM is lookng at with the KEY on. Was the KEY on????

 

[Ulysses]

Definitely the bottle in the facia.

The only sensor I can think of that I removed was the air sensor attached to the air filter box. I'm pretty sure the key was off.

Thanks,

Ulysses

 

[Rich Carlson]

I think the cause was the Air Temp Sensor. Make sure the sensor is connected and start the car, let it run a couple minutes. Shut it off and repeat a couple of times. See if the light goes out.

 

[Ulysses]

Thanks Rich,

I'll give her a go tonight.

Rich,

Just got back from a short run, stopping and starting here and there. The light went off, just as expected. Thanks again!

Ulysses