Rooster2 Posted October 22, 2016 Share Posted October 22, 2016 (edited) 99 Legacy Outback.......... Throwing check engine light code P1100, Starter Switch Circuit Low Imput was advised If the starter operates (which it does), there is an open, or ground short circuit between the ecm. and the starter motor connector. How do I trouble shoot this?? Car has stalled recently a couple of times at traffic lights. Suspect the problem involving the ecm is responsible for this. Car restarts easily after a stall. I need to fix this, before it gets worse. Any advise greatly appreciated. Thanx Edited October 22, 2016 by Rooster2 Link to comment Share on other sites More sharing options...
Fairtax4me Posted October 22, 2016 Share Posted October 22, 2016 Start signal circuit will not cause the engine to stall. That circuit only provides a signal to the ECU that the key has been turned to the start position. What exactly the ECU does with that signal I'm not sure of. The code is p1100, not p0100? Link to comment Share on other sites More sharing options...
ocei77 Posted October 22, 2016 Share Posted October 22, 2016 Battery cables tight? O. Link to comment Share on other sites More sharing options...
Rooster2 Posted October 23, 2016 Author Share Posted October 23, 2016 Battery cables tight? O. Will check that out............Thanx Link to comment Share on other sites More sharing options...
naru Posted October 23, 2016 Share Posted October 23, 2016 (edited) Rooster2, on 22 Oct 2016 - 13:22, said: 99 Legacy Outback.......... Throwing check engine light code P1100, Starter Switch Circuit Low Imput was advised If the starter operates (which it does), there is an open, or ground short circuit between the ecm. and the starter motor connector. How do I trouble shoot this?? Car has stalled recently a couple of times at traffic lights. Suspect the problem involving the ecm is responsible for this. Car restarts easily after a stall. I need to fix this, before it gets worse. Any advise greatly appreciated. Thanx It won`t be a ground short.The starter would not work. Check for opens/high resistances by unplugging thr ecu and putting your ohmmeter between the appropiate pin and the starter motor connector. Better yet,leave it plugged in and backprobe the connector w/a voltmeter. Pull the fuel pump fuse or relay. Note the voltage w/starter cranking. The ECU uses this signal to furthur enrich the mixture for starting. I have not seen it and I don`t follow the logic,but,apparently sometimes the ECU becomes confused when it does not see the start signal which causes subsequent running problems Something to think about. Edited October 23, 2016 by naru Link to comment Share on other sites More sharing options...
Rooster2 Posted October 23, 2016 Author Share Posted October 23, 2016 Good advise.............Thanks Link to comment Share on other sites More sharing options...
Rooster2 Posted October 23, 2016 Author Share Posted October 23, 2016 (edited) It won`t be a ground short.The starter would not work. Check for opens/high resistances by unplugging thr ecu and putting your ohmmeter between the appropiate pin and the starter motor connector. Better yet,leave it plugged in and backprobe the connector w/a voltmeter. Pull the fuel pump fuse or relay. Note the voltage w/starter cranking. The ECU uses this signal to furthur enrich the mixture for starting. I have not seen it and I don`t follow the logic,but,apparently sometimes the ECU becomes confused when it does not see the start signal which causes subsequent running problems Something to think about. If I do find a voltage drop, what is the solution to fix the problem?? Edited October 23, 2016 by Rooster2 Link to comment Share on other sites More sharing options...
Recommended Posts
Please sign in to comment
You will be able to leave a comment after signing in
Sign In Now