1993 Acura Vigor LS, AutomaticFACTORY OEM SERVICE PROCEDURE

Code 6: Coolant Sensor

  1. Turn ignition off. Remove BACK-UP (10-amp) fuse from underhood fuse/relay box for 10 seconds to reset ECM. Check ECM for fault codes. If Code 6 is not present, problem is intermittent. Check for poor and loose connections at coolant sensor, ECM and wiring harness. Test drive vehicle and retest.
  2. If Code 6 is present, operate engine until cooling fan comes on. Turn engine off. Disconnect connector from coolant sensor. Measure resistance between sensor terminals. If resistance is not 200-400 ohms, replace coolant sensor.
  3. If resistance is 200-400 ohms, turn ignition on. Measure voltage between sensor Yellow/Green wire terminal (+) and body ground. If about 5 volts are present, go to step 6. If voltage is not about 5 volts, go to step 4.
  4. On A/T models, disconnect 22-pin connector from Transmission Control Module (TCM). Turn ignition on. Recheck voltage at Yellow/Green wire terminal. If voltage is about 5 volts, replace TCM. If voltage is not about 5 volts, turn ignition off and reconnect TCM. On all models, connect connector "D" of ECM Test Harness (07LAJ-PT3010A ) to ECM, leaving vehicle wiring harness disconnected. Turn ignition on. Measure voltage between terminals D13 (+) and D22 (-). See Figure .
  5. If about 5 volts are present, repair open or short in Yellow/Green wire between ECM terminal D13, TCM (if equipped) and coolant sensor. If voltage is not about 5 volts, replace ECM and retest.
  6. If voltage was about 5 volts in step 3, measure voltage between sensor Yellow/Green and Green/White wires. If voltage is not about 5 volts, repair open in Green/White wire between ECM connector terminal D22 and coolant sensor. If about 5 volts are present, replace ECM and retest.
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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.