Oxygen Sensor Heater Test -P0141 (1996-1998 1.6L Suzuki Sidekick)

TEST 2: Testing The Heater Element's Resistance

After having checked the basics in the previous test, we'll check the rear O2 sensor heater's resistance with the multimeter in Ohms (Ω)mode.

NOTE: This test is done on the oxygen sensor's engine connector itself and NOT the engine wiring harness connector. This rear O2 sensor connector has male spade terminals.

CAUTION: Perform this test with a completely cold engine to avoid serious burns.

OK, this is what you need to do:

1. 1

   Disconnect the oxygen sensor from its connector.

2. 2

   Locate the outer 2 male terminals identified with the numbers 1 and 3 in the illustration above of the O2 sensor connector itself (not the engine wiring harness O2 connector).

3. 3

   With your multimeter in Ohms mode.

4. 4

   Probe terminals #1 and #3 of the O2 sensor itself with the multimeter test leads.

5. 5

   If all is OK, you should see about 11.7 to 14.3 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 specification. This test result tells you that rear oxygen sensor's heater is OK.

CASE 2: Your multimeter showed an open circuit (OL). This confirms that the downstream O2 sensor's heater element is fried. Replacing the downstream O2 sensor with a new one will solve the P0141 trouble code lighting up the check engine light (CEL).

Here are some more specifics: Since you have:

1. Confirmed that the rear O2 sensor's heater element is getting power (TEST 1).
2.      -AND-
3. Confirmed that the rear O2 sensor's heater element is getting Ground (TEST 2).
4.      -AND-
5. In this test you have confirmed that the heater element's resistance is out of specification.

Taking all of the above into account you can correctly conclude that the downstream O2 sensor, on your 1.6L Suzuki Sidekick (Geo Tracker), needs to be replaced with a new one.

More 1.6L Suzuki Tutorials

You can find a complete list of tutorials in this index: Suzuki 1.6L Index Of Articles.

Here's a small sample of the 1.6L Suzuki tutorials you'll find in the index:

• How To Test For A Blown Head Gasket (1.6L Suzuki Sidekick, Geo Tracker).
• How To Test The MAF Sensor (1992-1998 1.6L Sidekick).
• How To Test The Throttle Position Sensor (1996-1998 1.6L Sidekick).
• How To Test The Engine Compression (1.6L Suzuki Sidekick, Geo Tracker).
• 1996-1997 MAF Sensor Wiring Diagram (1.6L Sidekick / Tracker).