Entering On-Board Diagnostics (Using Voltmeter)

NOTE: Before proceeding with diagnosis, certain precautions must be followed. See PRETEST INSPECTION  .

1. 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 .
   Fig 1: Locating Diagnostic Connector

   Courtesy of CHRYSLER CORP.
2. 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.
3. Codes are displayed by 12-volt pulses of voltmeter pointer. A constant repetition of short 12-volt sweeps indicates system is normal.
4. 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.
5. 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 .
6. 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.

Fig 2: Identifying Voltmeter Signal Pattern

Courtesy of CHRYSLER CORP.

Fig 3: Diagnostic Fault Chart (1.8L)

Courtesy of CHRYSLER CORP.