p0141
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3rd Gear
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p0141
I have a 2001 coupe 6 speed. Recently got this code p0141, I cleared the codes and it came back on after a few miles. I guess it's supposed to be for the heater circuit on the driver rear o2 sensor. A mechanic at my work told me to check resistance with a multimeter for the 2 same color wires going into the sensor. I crawled underneath the car with ramps and I was able to test that it has 6.6 ohms resistance which I think he said was normal. No visible damage to the wires or connectors underneath the car. I couldn't find any specs for the actual resistance the heater is supposed to have. Anybody know what to do? Thanks.
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From: Cape Coral, Florida
You should have 3.5-14 ohms (coming from my service manual) on a cold sensor probing the same color wires at the sensor. The BROWN wire is power feed harness side and BLACK wire is a body ground...it goes to splice pack 122 (SP122) shown with battery and tray removed which is located at the back of the battery tray...remove the top of the SP by squeezing the ends of it and remove the “comb” and make sure there is no corrosion inside (comb shown removed)...from SP 122 it goes to a body ground ...with your voltmeter you can connect red lead to power wire (BROWN) and black lead to the black wire harness side (GROUND) and see if you read battery voltage...if good voltage you know the ground is good..if voltage low or 0 you have a bad ground...try that for now !’
Last edited by C5 Diag; May 25, 2019 at 09:46 AM.
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Joined: Sep 2013
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From: Cape Coral, Florida
NO...the splice pack is GROUND... Easiest thing is connect voltmeter to BROWN and BLACK on harness side...if voltage is the same as your battery voltage the ground is GOOD !!...if voltage is much
lower now you have to check for corrosion at the splice pack...all 4 O2 heater grounds go through this splice pack to a ground at the left engine block by the front O2 sensor...I use old headlight bulbs of different AMP ratings to “LOAD” the ground circuit depending on the circuit...my front O2 heater draws 1.556 AMPS at idle... if a 1.5 amp headlight bulb doesn’t light brightly when connected across the 2 wires I know I have ground issues !!
lower now you have to check for corrosion at the splice pack...all 4 O2 heater grounds go through this splice pack to a ground at the left engine block by the front O2 sensor...I use old headlight bulbs of different AMP ratings to “LOAD” the ground circuit depending on the circuit...my front O2 heater draws 1.556 AMPS at idle... if a 1.5 amp headlight bulb doesn’t light brightly when connected across the 2 wires I know I have ground issues !!
Last edited by C5 Diag; May 25, 2019 at 12:23 PM.
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From: Anthony TX
CI 6,7,8,9,11 Vet
St. Jude Donor '08
O2 sensor power
Once you check and clear the GROUNDS,, I recommend that you check the POWER to the O2 sensors. Find the OXY SEN Fuse #15 in the Under Hood fuse box. Use a DC Volt Meter and see what the voltage is on the two test points on top of the fuse. Measure each fuse to chassis ground or battery ground and see if you get full battery voltage. Use the TEST LAMP to se if the ignition contacts are providing proper CURRENT to power the heaters.
IGNITION SWITCH POWER OUTPUTS: Connector C2 Pin B supplies voltage to the heater circuit through the OXY SEN fuse 15.
Between C5 DIAG and myself,, POWER AND GROUND are covered!! LOL!!
Bill C
IGNITION SWITCH POWER OUTPUTS: Connector C2 Pin B supplies voltage to the heater circuit through the OXY SEN fuse 15.
Between C5 DIAG and myself,, POWER AND GROUND are covered!! LOL!!
Bill C
Last edited by Bill Curlee; May 25, 2019 at 12:34 PM.
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3rd Gear
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For whatever reason the check engine light was turned off when I started the car this morning. I checked the fuse which was good and took a look at the splice pack underneath the battery which was completely clean. I got underneath again and tested the brown and black wires and i was getting 12 volts and the test light lit up. I did notice that part of the sleeve for the wires on the o2 sensor was slightly melted on the exhaust but it didn't look like it went through. I'm hoping the light stays out and maybe it was just a bad connection since the check engine light went out after i was fiddling with the connector, there wasn't any corrosion in the connectors though. Thanks very much for the help guys, is there any further tests that can be done?
