Pinpoint Test A
Enter this test only when Codes 47, 48 or 49 are received in KEY ON, ENGINE OFF SELF-TEST. To prevent replacement of good components, the horn relay and/or fuses (non-IVSC areas) may be at fault. This pinpoint test is intended to diagnose only the speed control switches, brush assembly, slip ring assembly, wiring harness and the ECA.
- Service Code 47 appears. If "OFF", "COAST", "ACCEL" and "RESUME" buttons are pressed during IVSC KEY ON, ENGINE OFF, go to Step 2). If not, perform IVSC KEY ON, ENGINE OFF SELF-TEST.
- If switch does not function, turn key off. Wait 10 seconds. Disconnect ECA 60-pin connector. Inspect for damage. Service as necessary. Install Breakout box, leaving ECA disconnected. Measure resistance between test pin 50 and test pin 39 per table. If resistances are within range, replace ECA. If not, replace switches. If resistance values fluctuate within the ranges while steering wheel is rotated, or goes above ranges, clean brushes, slip rings and lubricate slip rings. If not, switches are okay.SABLE & TAURUS RESISTANCE RANGES
Range Button Ohm Resistance 200 Ohm "OFF" 0-4 200 Ohm "COAST" 114-126 2000 Ohm "ACCEL" 646-714 5000 Ohm "RESUME" 2090-2310 - Service Code 48 appears. If "OFF", "COAST", "ACCEL" and "RESUME" buttons are pressed during IVSC KEY ON, ENGINE OFF QUICK TEST, go to Step 4). If not, perform IVSC KEY ON, ENGINE OFF QUICK TEST.
- If switch is stuck with key off, wait 10 seconds. Disconnect ECA 60-pin connector. Inspect for damage. Service as necessary. Install Breakout box, leaving ECA disconnected. DVOM range should be on 5000-ohm scale. If resistance reading is 0-2310 ohms, replace switches. If not, replace ECA.
- Service Code 49 has appeared. If "OFF", "COAST", "ACCEL" and "RESUME" buttons are pressed during IVSC KEY ON, ENGINE OFF QUICK TEST, go to Step 6). If not, perform IVSC KEY ON, ENGINE OFF QUICK TEST.
- Turn key off and wait 10 seconds. Disconnect ECA 60-pin connector. Inspect for damage. Service as necessary. Install Breakout box, leaving ECA disconnected. Disconnect speed control switch plug in steering column shroud. Set DVOM on 200-ohm scale. Measure resistance between test pin 39 and ground terminal in 14290 harness (12-pin connector) half of disconnected switch plug. If resistance reading is greater than 5 ohms, service open circuit between EEC-IV connector pin 39 and switch plug ground terminal. If not, replace ECA. See Fig 1.