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P0140 on Jeep Gladiator

O2 Sensor Circuit No Activity (Bank 1 Sensor 2)

Factory diagnostic protocol and troubleshooting wire for fault code P0140 specifically for the Jeep Gladiator (2020–2026, 3.6L Pentastar V6 (285HP) / 3.0L EcoDiesel V6 (260HP 442 lb-ft) / Mojave).

Verified OEM Telemetry & Field Repair Tree
Jeep Gladiator2020–2026
Jeep Gladiator
Truck3.6L Pentastar V6 (285HP) / 3.0L EcoDiesel V6 (260HP 442 lb-ft) / Mojave
Reliability
Sensor Voltage Ref
0.1V – 5.0V Ref
Gladiator SAE Mode $01
ECU Network Bus
500 kbps CAN-FD
ISO 15765-4 Compliant
Drivability Status
Drivable (Short Trip)
Low urgency level
Est. Repair Cost
$100 - $300 (DIY: $35 - $100)
Parts & Labor DIY
Check P0140 On Another Jeep Model:
Diagnose P0140 on Specific Gladiator Model Year:

1. Symptoms of P0140 on Jeep Gladiator

When the Engine Control Module (ECM/PCM) on your Jeep Gladiator (3.6L Pentastar V6 (285HP) / 3.0L EcoDiesel V6 (260HP 442 lb-ft) / Mojave) logs fault code P0140, drivers commonly observe:

Check Engine Light on on Jeep Gladiator (3.6L Pentastar V6 (285HP) / 3.0L EcoDiesel V6 (260HP 442 lb-ft) / Mojave)
Downstream sensor flatlined at static 0.45V bias voltage on Jeep Gladiator (3.6L Pentastar V6 (285HP) / 3.0L EcoDiesel V6 (260HP 442 lb-ft) / Mojave)
Emissions readiness monitor incomplete on Jeep Gladiator (3.6L Pentastar V6 (285HP) / 3.0L EcoDiesel V6 (260HP 442 lb-ft) / Mojave)
Jeep Gladiator OBD-II Port Location
The 16-pin diagnostic connector is located Under driver dash near left knee kick panel. Plug in your scan tool to verify freeze-frame sensor values.

2. Most Likely Causes on Jeep Gladiator

Historical warranty claims and technical repair bulletins for Jeep Gladiator point to the following failure distribution:

55%
Completely dead downstream O2 sensor (Jeep OEM Part)
25%
Disconnected sensor harness plug under car (Jeep OEM Part)
12%
Cut or broken signal wire in vehicle harness (Jeep OEM Part)
8%
Corroded terminal pins in connector (Jeep OEM Part)
* Source: Synthesized from NHTSA ODI field repair telemetry and verified OEM Technical Service Bulletin (TSB) repair tree frequency percentiles for Jeep Gladiator.

3. Step-by-Step DIY Repair Guide for Jeep Gladiator

01
Check Sensor Connection Underbody

Inspect harness connector under vehicle floor pan. Verify plug is firmly seated and weather seal is intact. on the Jeep Gladiator equipped with 3.6L Pentastar V6 (285HP) / 3.0L EcoDiesel V6 (260HP 442 lb-ft) / Mojave.

Required Tool: Flashlight, Jack Stands
02
Test Sensor Heater & Signal Circuit

Check for 12V heater power and ground at connector with ignition ON. on the Jeep Gladiator equipped with 3.6L Pentastar V6 (285HP) / 3.0L EcoDiesel V6 (260HP 442 lb-ft) / Mojave.

Required Tool: Multimeter
03
Replace Downstream Oxygen Sensor

Remove and replace the downstream oxygen sensor with an OEM-spec part. on the Jeep Gladiator equipped with 3.6L Pentastar V6 (285HP) / 3.0L EcoDiesel V6 (260HP 442 lb-ft) / Mojave.

Required Tool: O2 Sensor Socket, Ratchet
04
Clear DTC Codes

Clear code and verify sensor activity returns on live telemetry. on the Jeep Gladiator equipped with 3.6L Pentastar V6 (285HP) / 3.0L EcoDiesel V6 (260HP 442 lb-ft) / Mojave.

Required Tool: OBD-II Scanner
Recommended Parts & Testing Tools

Equipment for Diagnosing Jeep Gladiator (P0140)

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Direct-Fit Replacement Part

Jeep Gladiator OEM Replacement Sensor

4.7 / 5.0 (Verified Fit)

Direct-fit replacement assembly engineered to OEM tolerances for Jeep Gladiator.

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Check Fitment on Amazon
Sensor Signal Voltage Meter

AstroAI Auto-Ranging Digital Multimeter

4.6 / 5.0 (Best Seller)

Essential for testing 0.1V–5.0V sensor reference signals, ground continuity (<0.20Ω), and harness resistance.

$29.99 Prime
View on Amazon
Top Mobile OBD-II Scanner

BlueDriver Bluetooth Pro OBDII Scan Tool

4.7 / 5.0 (50,000+ Reviews)

Reads and clears enhanced codes (ABS, Airbag, Transmission, Engine) & live freeze-frame telemetry on phone.

Compare OEM & Aftermarket Replacement Sensors for Jeep GladiatorVerified direct-fit pricing from Denso, Bosch, Motorcraft, and ACDelco on Amazon.
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Other Common Fault Codes on Jeep Gladiator

Frequently diagnosed powertrain, emissions, and sensor trouble codes logged on the Jeep Gladiator:

4. Jeep Gladiator P0140 FAQs

What causes code P0140 to trigger on a Jeep Gladiator?

On the Jeep Gladiator (3.6L Pentastar V6 (285HP) / 3.0L EcoDiesel V6 (260HP 442 lb-ft) / Mojave), P0140 is most frequently caused by Completely dead downstream O2 sensor or Disconnected sensor harness plug under car.

Where is the OBD-II port located on my Jeep Gladiator?

On the Jeep Gladiator, the 16-pin DLC diagnostic connector is located Under driver dash near left knee kick panel. Plug in any standard OBD-II scanner with the ignition in the ON position to read freeze-frame parameters.

Can I safely drive my Jeep Gladiator with code P0140?

Yes, safe for normal driving without risk of breakdown. Given that P0140 carries a Low severity rating, we advise avoiding heavy towing or aggressive throttle inputs until sensor readings are verified.