Test M - Neutral A/C Switch
- Code 67 Displayed. When this code is displayed, determine which engine and system is being tested and proceed to correct step as listed.
- For 2.3L EFI models with Man. Trans., go to step 5).
- For 2.9L & 3.0L EFI models, go to step 5).
- For 4.9L EFI models with Man. Trans., go to step 7).
- For all other models, go to next step.
- Turn key off and wait 10 seconds. Make sure heater control is in "OFF" position and that transmission is in Neutral or Park. Disconnect ECA 60-pin connector. Inspect for and repair any damaged wiring. Install breakout box and connect ECA. Turn key on, leaving engine off. Set DVOM on 20-volt scale and measure voltage between test pin 30 and chassis ground. If reading is less than 1.0 volt, go to step 4). If reading is 1.0 volt or higher, go to next step.
- Turn key off and wait 10 seconds. Leave breakout box installed and ECA connected. Locate neutral drive switch and disconnect harness at switch. Set DVOM on 200-ohm scale and measure resistance across switch. If reading is less than 5 ohms, repair open in neutral drive switch circuit. Repeat QUICK TEST . If reading is 5 ohms or more, replace neutral drive switch and repeat QUICK TEST .
- Install breakout box and connect ECA. Turn key on, leaving engine off. Set DVOM on 20-volt scale, and turn A/C control switch off. Measure voltage between test pin 10 and chassis ground. If reading is 1.0 volt or more, repair short to power in A/C clutch circuit. Repeat QUICK TEST . If reading is less than 1.0 volt, replace ECA and repeat QUICK TEST .
- Turn key off and wait 10 seconds. Make sure that A/C is off, if equipped. Ensure that transmission is in Neutral and that clutch is released. Disconnect ECA 60-pin connector. Inspect for and repair any damaged wiring. Install breakout box and connect ECA. With DVOM on 200-ohm scale, measure resistance between test pins 30 and 46. If reading is less than 5 ohms, go to step 4). If reading is 5 ohms or more, go to next step.
- Turn key off. With breakout box and ECA connected, set DVOM on 200-ohm scale. Locate neutral switch (on transmission) and clutch switch (under dash). Disconnect wiring harness from both switches. Measure resistance across each switch. If reading at both switches is less than 5 ohms, go to next step. If reading at either or both switches is 5 ohms or more, replace defective switch(es). Connect harness and repeat QUICK TEST .
- Turn key off. Set DVOM on 200-ohm scale and install breakout box. Disconnect vehicle harness at neutral switch and clutch switch. Measure resistance between pin No. 30 and neutral switch harness connector and between pin No. 46 and clutch switch harness connector. Also measure resistance between pin No. 46 and neutral switch harness connector and between pin No. 46 and clutch switch harness connector. If readings are more than 5 ohms, repair harness/connector and repeat QUICK TEST . If readings are less, repeat step 4).
- Clutch Pedal Switch Test 4.9L M/T. Turn key off and wait 10 seconds. Depress clutch pedal. Verify that A/C switch is off (if equipped). Disconnect ECA 60-pin connector. Inspect for and repair any damaged wiring. Install breakout box and connect ECA. Set DVOM on 20 volt scale. Measure resistance between test pin No. 30 and neutral input circuit at SELF-TEST connector. If reading is less than 5 ohms, go to step 4). If reading is 5 ohms or more, repair open in clutch circuit.
- A/C Input Circuit Check. Turn key off, wait 10 seconds. Remove ECA pin connector and inspect for damage. Repair as necessary. Install breakout box but leave ECA disconnected. Set DVOM on 20-volt scale. Turn key on and turn on A/C. Check voltage between pins No. 10 and 40. If voltage is greater than 10.5 volts, replace ECA and repeat QUICK TEST . If voltage is lower than 10.5 volts, service open in A/C circuit. Repeat QUICK TEST .
