Oxygen Sensor Heater Test -P0141 (1997-2001 2.0L Honda CR-V)

TEST 2: Testing The Heater Element's Resistance

In the previous test section you made sure that the O2 sensor is getting power and Ground.

Now we're gonna' make sure that rear O2 sensors heater element's resistance is within specification. This specification is 10 to 40 Ohms.

If the heater element is not within factory specifications, then you can conclude that the O2 sensor is fried and needs to be replaced with a new one.

NOTE: Perform this test with a completely cold engine. Specially because the heater element specification is with the rear O2 sensor at room temperature..

OK, this is what you need to do:

1. 1

   Using the illustration above, locate O2 sensor terminals 3 and 4 of the O2 sensor connector itself (not the engine wiring harness O2 connector).

2. 2

   With your multimeter in Ohms (Ω) mode, probe terminals 3 and 4 of the O2 sensor itself.
   
   Remember, you'll probe the male terminals of the O2 sensor's connector and not the female terminals of the engine wiring harness connector.

3. 3

   If all is OK, you should see about 10 to 40 Ωs on your multimeter.
   
   If the heater element is fried, your multimeter will show an open (usually indicated by the letters OL) or a number over 10 K Ωs.

Let's take a look at your test results:

CASE 1: The rear O2 sensor's heater resistance is within spec. This is the correct and expected test result.

Since you have confirmed that the rear O2 sensor is getting power and Ground and that its resistance specification is OK, you can conclude that the O2 sensor is not defective.

CASE 2: Your multimeter showed an open circuit (OL). This test result tells you that the O2 sensor's heater element is defective.

Since you have checked and confirmed that the O2 sensor is getting power and Ground and that its resistance IS NOT within specification, you can replace it with a new one.

More 2.0L Honda Tutorials

You can find a complete list of tutorials here: Honda 2.0L Index Of Articles.

Here's a sample of the tutorials you'll find there:

• How To Test The Ignition Coil (1997-1998 2.0L Honda CR-V).
• How To Test The TPS (1997-2001 2.0L Honda CR-V).
• How To Test The MAP Sensor (1997-2001 2.0L Honda CR-V).
• How To Test Engine Compression (1997-2001 2.0L Honda).

On YouTube, check out my following videos:

• How To Test The Ignition Coil (1999-2001 2.0L Honda CR-V) (at YouTube).
• How To Test The Ignition Control Module (1999, 2000, 2001 2.0L Honda CR-V) (at YouTube).
• How To Test The Fuel Pump (1997-2001 2.0L Honda CR-V) (at: YouTube).