P0140 Code
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P0140 Code
I have looked this up online and this is what I have come up with...
http://www.obd-codes.com/p0140
Does anyone after reading that link know what I should try to fix first so that this code goes off. Car def. uses a lot more gas with the check engine light on...
Please let me know
All Star
Joined: Nov 2007
Posts: 807
Likes: 9
From: Raleigh, NC
First off, the italics are annoying to read.
Second, what year and trim do you have? How many doors does your car have? Crucial information.
Third, it tells you exactly how to fix this issue.
You cant fix a bad O2 sensor. If the code comes up, replace the sensor. They arent that expensive usually.
Second, what year and trim do you have? How many doors does your car have? Crucial information.
Third, it tells you exactly how to fix this issue.
Possible Solutions
This is a fairly specific problem and shouldn't be too difficult to diagnose.
First, start engine and warm up. Using a scan tool, watch the Bank 1, sensor 2, o2 sensor voltage. Normally the voltage should switch slowly above and below .45 volts. If it does, the problem is likely intermittent. You'll have to wait for the problem to surface before you can accurately diagnose.
However, if it doesn't switch, or is stuck then perform the following: 2. Shut off vehicle. Visually check the Bank1,2 harness connector for melting or chafing of the harness or the connector. Repair or replace as needed 3. Turn ignition on, but engine off. Disconnect the O2 sensor connector and check for 12Volts at the Heater Circuit supply and for proper ground on the heater circuit ground circuit. a. If 12V heater supply is missing, check the proper fuses for an open in the circuit. If heater circuit fuse is blown, then suspect a bad heater in the o2 sensor causing a blown heater circuit fuse. Replace sensor and fuse and recheck. b. If ground is missing, trace the circuit and clean or repair ground circuit. 4. Next, with connector still unplugged, check for 5 Volts on the reference circuit. If this is missing, check for 5 Volts at the PCM connector. If 5 Volts is present at the PCM connector but not at the o2 sensor harness connector, then there is an open or short in the reference wire supply between the PCM and the o2 sensor connector. However, if there is no 5 Volts present at the PCM connector, the PCM is likely at fault due to internal short. Replace PCM. ** (NOTE: on Chrysler models, a common problem is the 5Volt reference circuit can be shorted out by any sensor on the car that uses a 5 Volt reference. Simply unplug each sensor one at a time until the 5 Volts reappears. The last sensor you unplugged is the shorted sensor. Replacing it should fix the 5 Volt reference short.) 5. If all the voltages and grounds are present, then replace the Bank 1,2 O2 sensor and re-test.
This is a fairly specific problem and shouldn't be too difficult to diagnose.
First, start engine and warm up. Using a scan tool, watch the Bank 1, sensor 2, o2 sensor voltage. Normally the voltage should switch slowly above and below .45 volts. If it does, the problem is likely intermittent. You'll have to wait for the problem to surface before you can accurately diagnose.
However, if it doesn't switch, or is stuck then perform the following: 2. Shut off vehicle. Visually check the Bank1,2 harness connector for melting or chafing of the harness or the connector. Repair or replace as needed 3. Turn ignition on, but engine off. Disconnect the O2 sensor connector and check for 12Volts at the Heater Circuit supply and for proper ground on the heater circuit ground circuit. a. If 12V heater supply is missing, check the proper fuses for an open in the circuit. If heater circuit fuse is blown, then suspect a bad heater in the o2 sensor causing a blown heater circuit fuse. Replace sensor and fuse and recheck. b. If ground is missing, trace the circuit and clean or repair ground circuit. 4. Next, with connector still unplugged, check for 5 Volts on the reference circuit. If this is missing, check for 5 Volts at the PCM connector. If 5 Volts is present at the PCM connector but not at the o2 sensor harness connector, then there is an open or short in the reference wire supply between the PCM and the o2 sensor connector. However, if there is no 5 Volts present at the PCM connector, the PCM is likely at fault due to internal short. Replace PCM. ** (NOTE: on Chrysler models, a common problem is the 5Volt reference circuit can be shorted out by any sensor on the car that uses a 5 Volt reference. Simply unplug each sensor one at a time until the 5 Volts reappears. The last sensor you unplugged is the shorted sensor. Replacing it should fix the 5 Volt reference short.) 5. If all the voltages and grounds are present, then replace the Bank 1,2 O2 sensor and re-test.