What does this code mean? How do I fix it?

 

This is a 2001 Legacy AWD sedan 5-speed. I'm not sure what a "neutral circuit switch" means in a car with a manual transmission...

 

Thanks,

 

Jeff in Boston

Manual transmissions have a switch on the clutch-pedal, so that the starter-motor will not energize unless the pedal is fully dressed.

 

Does your starter operate as normal with your foot on the clutch-pedal?

Im pretty sure the switch on the pedal is just for cruise control. My 96 and 99 have a neutral safety switch on the driver side of the transmission so I assume that yours would as well. The switch is a 2 wire round screw in switch thats next to the backup switch that is identical except the backup connector is brown and the Neutral is grey. Those switch connectors are on a bracket on either the passenger top engine to tranny bolt or right above it on the engine hoist loop bolt. Had to replace mine last week although the code was different but it came up as a neutral safety switch. (actually it came up as a IAC but the NSS threw it)

Edited March 23, 201610 yr by gravitate

This is a switch on the side of the manual transmission, like the backup light switch.

 

Dealer only item, pretty inexpensive and easy to change. High enough on the trans that you will not leak any fluid.

 

Purpose, , to tell the ECU when you are in Neutral, so either you are decelerating or the ECU must control the Idle.

 

Example, you are driving WITHOUT your foot on the gas, Car in gear, The ECU doesn't have to control the idle.

 

You shift into neutral, NOW the ECU MUST control the idle.

 

It's detected as a fault when the switch is bad ... you are IN GEAR, without foot on the gas, but the ECU DOESN'T KNOW IT, so the ECU now tries to control the idle AND IT CAN'T. So it thinks it's at a HIGH UNCONTROLLABLE IDLE.

 

Older manuals usually call out IAC , TPS and other Idle controls for this error.

X2 what Ferret said. You'll see two switches screwed into the transmission case on the drivers side. The neutral switch is the furthest to the rear. 

 

 

Clutch safety switch on the pedal has NOTHING to do with this code. 

Encountered same issue, including false IAC code P0505.  Once I swapped neutral switch, both codes cleared. 

 

Thanks for shedding light on the IAC subject.  Great forum!