P0197

Code

LAND ROVER P — Powertrain

low circuit of engine oil temperature sensor

Brand: LAND ROVER

Type: P — Powertrain

Views: UK: 32 EN: 45 RU: 51

AI status

Completed

ready

Completed 100%

Page language: EN

Causes

Short to ground in the EOT sensor signal wire
Failed/shorted engine oil temperature sensor (thermistor)
Corroded, contaminated or loose sensor connector
Damaged wiring harness (chafing, pinched, exposed conductor)
Oil intrusion into the connector causing a short
Faulty ECM/PCM input (rare) or ground problem elsewhere

Symptoms

MIL (Check Engine Light) illuminated
Incorrect or implausible oil temperature reading in scan tool (very low or stuck value)
Possible engine warm-up or cold-start issues if ECM uses oil temp for control
Stored freeze-frame data showing low sensor voltage or low temperature
No other drivability symptoms in many cases

What to check

Read freeze-frame and freeze data with a scan tool; record live EOT sensor values and related temps
Perform visual inspection of sensor, connector and harness for corrosion, oil saturation, chafing or damage
Backprobe sensor connector with key ON (engine OFF) and measure signal voltage relative to ground
Measure sensor resistance at ambient temp (with sensor removed) and compare to specification or expected thermistor behavior
Check for continuity between signal wire and ECM and for short to ground
Inspect ECM ground and power supplies if wiring checks good

Signal parameters

Sensor type: usually NTC thermistor — resistance decreases as temperature rises (manufacturer-specific curve)
Typical control: ECM reads 0–5 V signal (varies by vehicle); a low-circuit fault will show a very low voltage (example:
Resistance examples (generic): very high at cold/high resistance (kΩs), lower at higher temps (hundreds to low kΩ) — consult Land Rover spec for exact values
Short-to-ground condition: signal near 0 V and resistance measurement may read near 0 Ω between signal and ground
Open-circuit condition (for comparison): signal often pulled high by ECM and may measure near reference voltage (example: >4.0 V)

Diagnostic algorithm

Retrieve and record all codes, freeze-frame and live EOT data with a capable scan tool.
Visually inspect sensor, connector and harness for oil contamination, corrosion, bent pins, burns, chafing or physical damage. Repair any obvious damage and retest.
With ignition ON (engine OFF) backprobe the sensor connector: measure reference voltage (if applicable), signal voltage and sensor ground. Note readings.
Remove the sensor and measure its resistance at ambient temperature. Verify resistance changes when sensor warmed/cooled (hot water or ambient temperature change) consistent with thermistor behavior. Compare to Land Rover specification if available.
If sensor reads near 0 Ω or signal stays near 0 V, suspect a short to ground in the signal circuit. Perform continuity test from signal pin to chassis ground to confirm.
If sensor resistance is within spec but signal is low at connector, check continuity of signal wire from connector to ECM and inspect for shorts to ground along the harness (wiggle test while monitoring signal can help locate intermittent faults).
If wiring and sensor are good, check ECM connector pin for proper voltage/ground and consider ECM input fault (verify with service information before replacing ECM).
Replace failed sensor or repair wiring/connector as required. Clear codes, perform readiness procedures and road test while monitoring live EOT data to confirm repair.
If problem persists after replacing sensor and repairing wiring, consult manufacturer diagnostic documentation for ECM-level tests or consider controlled substitution/testing of PCM only after all other possibilities are excluded.

Likely causes

Failed oil temperature sensor
Signal wire shorted to ground or damaged near sensor
Corroded/contaminated connector at sensor
Harness damage at common failure points (near oil filter, pan, or engine mounts)

Fault status

⚠️ Status

ECM detected engine oil temperature sensor circuit voltage lower than expected (signal low / possible short to ground).

🟡 Repair difficulty: Medium

⏱️ Diagnostic time: 0.5-1.5 hours

Similar codes

Repair manuals

Manual library for LAND ROVER

413

Browse 413 LAND ROVER manuals: repair procedures, diagnostics, wiring diagrams, component locations, service data and Labor Times by year, model and trim.

LAND ROVER

Your experience will help others

+100 karma for a short comment :)

Was this AI description helpful?

Your feedback helps improve AI descriptions.

👍 Like 0 👎 Dislike 0

Send to email

P0197 — low circuit of engine oil temperature sensor