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Home >> Ford >> 1989 >> Ranger 2D Pickup Extra Cab, 2.3 A, M5OD-R1 >> Repair and Diagnosis >> Engine Performance >> System >> 2.3L CEC Tests W/Codes >> Circuit Tests >> Dis Memory Code 18 - Coil Failure
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Dis Memory Code 18 - Coil Failure

  1. 48)  Using Neon Spark Tester (Champion CT-436 ), check for spark at each spark plug wire with engine running. If spark is present at all wires, go to step 61). If spark is not present at all wires, go to next step.
  2. 49)  Check Spark On Right Side. If spark was present on all right side wires, go to next step. If not, go to step 57).
  3. 50)  Isolate Left Spark Fault. If spark was missing from both 1 and 4 cylinder or both 2 and 3 cylinders, go to step 52). If spark was not missing, go to next step.
  4. 51)  Checking Left Plugs And Wires. Check left spark plug wires for damage. Remove and check left spark plugs. Replace or repair any damaged component(s) and repeat QUICK TEST. If spark plugs and wires are okay, reinstall and connect components and go to next step.
  5. 52)  Left Spark Fault Module Output Check. Turn key off. Install diagnostic cable to breakout box with proper "OVERLAY" used. Disconnect diagnostic cable connector from DIS module pins 7-12. Connect a jumper between J55 (IGND S) and J60 (VBAT-). Connect a jumper between J54 (DPI) and J55 (IGND S). If spark was missing from cylinders 1 and 4, connect LED test light positive lead to J5 (VBAT D) and negative lead to J3 (LC3D). If spark was missing from cylinders 2 and 3, connect LED test light positive lead to J5 (VBAT D) and J6 (LC4D). If test light blinks continuously during cranking, go to next step. If test light did not blink, replace DIS module and repeat QUICK TEST.
  6. 53)  Left Spark Fault, Left Coil Pack VBAT Check. Turn key off. Remove jumpers. Reconnect diagnostic cable connector to DIS module pins 7-12. Connect LED test light positive lead to J15 (VBAT L) and negative lead to J60 (VBAT-). Turn key on. If test light is on, go to next step. If test light is not on, repair or replace wiring as necessary and repeat QUICK TEST.
  7. 54)  Left Spark Fault, Isolate Left Coil Pack. Turn key off. Disconnect HEGO sensor. Disconnect diagnostic cable connector from the left coil pack. If spark was missing from cylinders 1 and 4, connect LED test light positive lead to J57 (VBAT+) and negative lead to J30 (LC3C). If spark was missing from cylinders 2 and 3, connect LED test light positive lead to J57 (VBAT+) and negative lead to J28 (LC4C). Crank engine. If test light blinks continuously while cranking or engine running, replace left coil pack and repeat QUICK TEST. If test light does not blink, go to next step.
  8. 55)  Left Spark Fault, Check For Open. Disconnect diagnostic cable connector from DIS module pins 7-12. If spark was missing from cylinders 1 and 4, measure resistance between J3 (LC3D) and J30 (LC3C). If spark was missing from cylinders 2 and 3, measure resistance between J6 (LC4D) and J28 (LC4C). If either resistance is less than 5 ohms, go to next step. If resistance is not less than 5 ohms, repair or replace open wire between left coil pack and DIS module and repeat QUICK TEST.
  9. 56)  Left Spark Fault, Check For Shorts. If spark was missing from cylinders 1 and 4, measure resistance between J3 (LC3D) and J57 (VBAT+). If spark was missing from cylinders 2 and 3, measure resistance between J6 (LC4D) and J57 (VBAT+). If either resistance is less than 10K ohms, repair or replace shorted wiring to VBAT between DIS module and coil pack and repeat QUICK TEST. If resistance is not less than 10K ohms, repair or replace shorted wiring to ground between left coil pack and DIS module and repeat QUICK TEST.
  10. 57)  Right Spark Fault, Check Module Output. Turn key off. Disconnect HEGO sensor. Install diagnostic cable. Disconnect diagnostic cable connector from DIS harness pins 7-12. Connect diagnostic cable to breakout box, using proper "OVERLAY". Connect jumper between J55 (IGNDS) and J60 (VBAT-). If spark was missing from cylinders 1 and 4, connect LED test light positive lead to J57 (VBAT+) and negative lead to J18 (RC1D). If spark was missing from cylinders 2 and 3, connect LED test light positive lead to J57 (VBAT+) and negative lead to J10 (RC2D). If test light blinks continuously while cranking engine, go to next step. If test light does not blink, replace DIS module and repeat QUICK TEST.
  11. 58)  Right Spark Fault, Isolate Right Coil Pack. Turn key off. Connect diagnostic cable connector to DIS module pins 7-12. Disconnect diagnostic cable connector from right coil pack. If spark was missing from cylinders 1 and 4, connect LED test light positive lead to J57 (VBAT+) and negative lead to J23 (RC1C). If spark was missing from cylinders 2 and 3, connect LED test light positive lead to J57 (VBAT+) and negative lead to J24 (RC2C). If test light blinks continuously while cranking engine, go to next step. If test light does not blink, replace DIS module and repeat QUICK TEST.
  12. 59)  Right Spark Fault, Check For Open. Turn key off. Disconnect diagnostic cable connector from DIS module pins 7-12. If spark was missing from cylinders 1 and 4, measure resistance between J18 (RC1D) and J23 (RC1C). If spark was missing from cylinders 2 and 3, measure resistance between J10 (RC2D) and J23 (RC1C). If either resistance is less than 5 ohms, go to next step. If resistance is not less than 5 ohms, repair or replace open wire between DIS module and coil pack. Repeat QUICK TEST.
  13. 60)  Right Spark Fault, Check For Shorts. Disconnect HEGO sensor. If spark was missing from cylinders 1 and 4, measure resistance between J18 (RC1D) and J60 (VBAT-). If spark was missing from cylinders 2 and 3, measure resistance between J10 (RC2D) and J60 (VBAT-). If either resistance is less than 10K ohms, repair or replace short to ground between DIS module and coil pack and repeat QUICK TEST. If resistance is not less than 10K ohms, repair or replace short to VBAT between DIS module and coil pack and repeat QUICK TEST.
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