Entering On-Board Diagnostics (Using Voltmeter)
WARNING: This page is about a different car, the 1994 Plymouth Laser and 1994 Eagle Talon. However, it is still accessible from the selected car via links, so may be relevant.
NOTE:
Before proceeding with diagnosis, certain precautions must be followed. See PRETEST INSPECTION .
- Turn ignition off. Using an analog voltmeter, connect voltmeter positive lead to self-diagnostic connector terminal No. 1 and negative lead to terminal No. 12 (ground). Diagnostic connector is located next to junction block, above left kick panel. See Fig 1.
- Ensure all accessories are off. Turn ignition switch to ON position. Disclosure of ECU memory will begin. If 2 or more systems are non-functional, they are displayed in order of increasing code number.
- Codes are displayed by 12-volt pulses of voltmeter pointer. A constant repetition of short 12-volt sweeps indicates system is normal.
- If system is abnormal, voltmeter will pulse between zero and 12 volts. Fault codes will appear on voltmeter as long and short 12-volt sweeps. Long sweeps represent tens; short sweeps represent ones.
- For example, one long sweep followed by a short pause followed by 4 short sweeps would indicate Code 14. See Fig 2. After recording fault codes, perform necessary repair according to appropriate diagnostic fault chart. See Fig 3 or Fig 4.
- After repair, turn ignition off. Disconnect negative battery cable for 10 seconds to erase ECU fault codes. Reconnect negative battery cable, and enter on-board diagnostics to confirm repair. Ensure no fault codes are stored.