Toggle Side Panel

Shopping Cart

No products in the basket.

Shopping Cart

No products in the basket.

Close search
Home / DTC / B1019 — Heater water TEMP. SNSR.inactive

B1019 — Heater water TEMP. SNSR.inactive

Detailed page for trouble code B1019.

34,660codes
59brands
11,925generic
22,735specific
All codes P-codes (Powertrain) B-codes (Body) C-codes (Chassis) U-codes (Network/User) Tesla Alerts
Reset
Code

B1019

MITSUBISHI B — Body

Heater water TEMP. SNSR.inactive

Brand: MITSUBISHI
Type: B — Body
AI status
Completed
ready
Completed 100%
Page language: EN

Causes

  • Open or shorted sensor circuit (broken wire, chafing, pinched harness)
  • Disconnected, corroded, or water-damaged connector at the sensor or ECU
  • Failed heater water temperature sensor (NTC thermistor or similar)
  • Blown fuse or faulty relay supplying sensor/heater electronics
  • Faulty body control module / heater control module or poor ECU ground
  • Intermittent wiring fault (moisture ingress, damaged insulation)

Symptoms

  • Auxiliary heater/parking heater may not operate or may run in default mode
  • Cabin heating reduced or no warm air from heater
  • DTC B1019 stored in body ECU; possible MIL or dash message related to heater
  • Heater control displays incorrect or no temperature value for heater circuit
  • Intermittent heater operation if wiring is intermittent

What to check

  • Read fault code and live data with a scan tool; note freeze-frame and any related codes
  • Visually inspect sensor connector and wiring for corrosion, damage, or water ingress
  • Check related fuses and relays for the heater/control module circuit
  • Backprobe sensor connector with ignition on to verify reference voltage and ground
  • Measure sensor resistance at ambient temperature and compare to specification
  • Perform continuity check between sensor connector and body ECU connector

Signal parameters

  • Sensor type: typically an NTC thermistor (resistance decreases as temperature increases)
  • Expected electrical behavior: analog signal in 0–5 V range to the body/heater ECU
  • Resistance guidance (typical, vehicle-specific): at ~20°C resistance often in the low kΩ range; open circuit >> MΩ, short ~0–100 Ω
  • A completely inactive sensor will show no returning signal (open/high resistance) or constant voltage stuck at rail

Diagnostic algorithm

  1. Connect a capable scan tool and confirm B1019 and any related codes (record freeze-frame and live heater temp PID).
  2. Inspect sensor connector and harness for corrosion, debris, broken pins, or water entry. Repair or clean as needed.
  3. Verify power and ground to the sensor circuit (check fuses/relays and measure reference voltage with ignition ON).
  4. Unplug sensor and measure sensor resistance at ambient temperature; compare with factory spec. If open or shorted, replace sensor.
  5. If resistance is within spec, backprobe the sensor connector with sensor connected and monitor voltage or resistance while warming sensor (steam or warm coolant) to confirm changing value.
  6. Check continuity between sensor connector and body/heater ECU connector; repair any opens or high-resistance joints.
  7. If wiring and sensor test good, inspect ECU grounds and connectors; consider swapping or bench-testing heater control module only if service information supports this.
  8. After repairs, clear codes, perform functional test of heater, and re-check for code reappearance and correct live data behavior.
  9. If intermittent, perform extended drive or soak tests and monitor live data while manipulating wiring to reproduce the fault.

Likely causes

  • Failed or shorted heater water temperature sensor
  • Loose, corroded or disconnected connector at the sensor
  • Open or damaged wiring between sensor and body ECU
  • Blown fuse or missing power/ground to sensor circuit

Fault status

⚠️ Status
Heater water temperature sensor inactive — no valid signal from the heater coolant temperature sensor to the body/heater control module.
🟡 Repair difficulty: Medium
⏱️ Diagnostic time: 0.5-2.0 hours

Similar codes

B1018 B1020 P0115 P0117 P0118
406

Browse 406 MITSUBISHI manuals: repair procedures, diagnostics, wiring diagrams, component locations, service data and Labor Times by year, model and trim.

MITSUBISHI

Your experience will help others
+100 karma for a short comment :)
Keep it short and practical. Up to 500 characters.
Send to email

Report

Harassment or bullying behavior
Contains mature or sensitive content
Contains misleading or false information
Contains abusive or derogatory content
Contains spam, fake content or potential malware

Block Member?

Please confirm you want to block this member.

You will no longer be able to:

  • See blocked member's posts
  • Mention this member in posts
  • Invite this member to groups
  • Message this member
  • Add this member as a connection

Please note: This action will also remove this member from your connections and send a report to the site admin. Please allow a few minutes for this process to complete.

Report

You have already reported this .