legosti Posted April 5, 2015 Share Posted April 5, 2015 I'm trying to install a bosch universal 3 wire 15726 downstream o2 on my gf's 97 legacy 2.5 but the org. Was a 4 wire? Anyone else run into this? It's a bosh 15726. Thanks! Quote Link to comment Share on other sites More sharing options...
legosti Posted April 5, 2015 Author Share Posted April 5, 2015 I figured it out.Bosch 3 wire is signal(black), heater+(white)and heater-(white) . 4 wire is all those plus sensor ground(grey). Anyone have any experience with switching the 4 wire for a 3 on the downstream? Quote Link to comment Share on other sites More sharing options...
Fairtax4me Posted April 5, 2015 Share Posted April 5, 2015 (edited) If the downstream has 4 wires then the replacement has to be a 4 wire sensor. No easy way around it. Take it back and exchange it for the correct sensor. Some of these have a 4 wire plug for the rear sensor, but only three wires in the plug. Check the sensor harness carefully because there may be 4 wires in the extension harness that runs alongside the trans, but only 3 wires on the actual sensor. Edited April 5, 2015 by Fairtax4me Quote Link to comment Share on other sites More sharing options...
legosti Posted April 6, 2015 Author Share Posted April 6, 2015 Original sensor has 4 wires, most aftermarket are 3 , missing that grey ground. Cel is off, grey wire not connected. Quote Link to comment Share on other sites More sharing options...
Recommended Posts
Join the conversation
You can post now and register later. If you have an account, sign in now to post with your account.