2000 Mazda MPV DXFACTORY OEM SERVICE PROCEDURE

DTC P0118: ECT Sensor Input High: Testing

NOTE: Ensure freeze frame data has been recorded. Check for service bulletins and on-line information.
  1. Connect scan tool. Turn ignition on. Check ECT V PID. If PID is more than 4.6 volts, go to next step. If PID is 4.6 volts or less, problem is not present. Check for intermittent problem. See TROUBLE SHOOTING - NO CODES article.
  2. Turn ignition off. Remove air cleaner. Disconnect ECT sensor, located above starter. Check ECT sensor connector terminals. If connectors are okay, go to next step. If connectors are faulty, repair as necessary and go to step  8 .
  3. Connect a jumper wire between harness connector terminals No. 1 and No. 2. Check ECT V PID. If PID is not about zero volts, go to next step. If PID is about zero volts, replace ECT sensor. After repair, go to step  8 .
  4. Turn ignition on. Check voltage between sensor harness connector terminal No. 1 (White/Green wire) and ground. If battery voltage is not present, go to next step. If battery voltage is present, repair short to power. After repair, go to step  8 .
  5. Turn ignition off. Disconnect PCM connector. PCM is mounted to passenger floor, behind glove box. Check connector terminals No. 38 and No. 91. If no problem is found, go to next step. If terminals are faulty, repair as necessary. After repair, go to step  8 .
  6. Connect breakout box to harness connector. Leave PCM disconnected. Check continuity between ECT sensor harness connector terminal No. 1 and breakout box terminal No. 38. If continuity is present, go to next step. If continuity is not present, repair open in White/Green wire or Red/Blue wire. After repair, go to step  8 .
  7. Check continuity between ECT sensor harness connector terminal No. 2 (Brown/Green wire) and breakout box terminal No. 91. If continuity is present, go to next step. If continuity is not present, repair open in circuit. After repair, go to next step.
  8. Reconnect all components. Turn ignition on. Using scan tool, clear DTC. Start engine. Recheck DTCs. If DTC P0118 is present, replace PCM and go to next step. If DTC P0118 is not present, go to next step.
  9. Perform after repair procedure. See AFTER REPAIR PROCEDURE  . If no DTC is present, testing is complete. If any DTC is present, go to appropriate test for diagnosis and repair.
Factory Service Tools

Use the Manual With the Right Hardware

Pair factory procedures with proven DIY tools so the instructions are easier to execute.

Disclosure: Verified tool recommendations may earn an affiliate commission at no cost to you.

Shop Manual-Ready ToolsCompare Repair QuoteQuote Shield Pro

When to See a Mechanic

Stop DIY work and contact a certified mechanic immediately if any of the following apply:

  • • You smell fuel, burning insulation, or see smoke.
  • • Brakes feel soft, pull hard to one side, or make grinding noises.
  • • The engine overheats, stalls repeatedly, or misfires under load.
  • • You are missing required tools, torque specs, or safe lifting equipment.
  • • You are not confident in the next step or safety outcome.

Rather have a pro handle this?

A certified mobile mechanic comes to your home or office. They bring the tools, you stay comfortable. No tow truck, no waiting room, no surprises.

Comes to youSame-day available12-month warranty
Get a Free Quote

No obligation. See pricing before you book.