With Impulse Counter

On-Board Diagnostic Readout with Impulse Counter
Model Year 1988 California Vehicles only

Complaint: "CHECK ENGINE" warning lamp in instrument cluster comes on.

Test Requirement: Do not disconnect battery, overvoltage protection relay or CIS-E control unit before or during the test, otherwise the stored malfunction will be erased from memory. Battery voltage: 11-14 Volts.

Special Tools





Equipment
Digital multimeter -- Available through the MBNA Standard Equipment Program.
^ Manufacturers: SUN DMM-5, Fluke model 23

Malfunction Diagnostic Table:

X92 Test connection for diagnosis (8-pole, impulse readout):

- Connect test equipment according to figure.
013 Impulse counter
G1 Battery
X92 Test connection for diagnosis (8-pole, impulse readout)

NOTE: When using the impulse counter:
^ The number "1" indicates that there are no stored malfunctions in the system's memory. All other numbers refer to a particular malfunction source. If there are multiple system malfunctions, the malfunction with the lowest assigned impulse number will be indicated first.

^ Numbers ranging from 1 to 10 appear on the impulse counter indicator.

^ The LED "U Batt" is illuminated after connecting the impulse counter; this indicates the impulse counter and its voltage supply are in proper working order.

^ During a system test, if no additional readout (number) appears after the initial one or more impulse readouts (numbers), this indicates no further malfunctions are stored in memory.

Checking system
- Connect impulse counter according to figure.
- Switch ignition on.

NOTE: LED "U Batt" must be displayed on the indicator, if not proceed as follows:

- With multimeter in position "Volt"
a) Test for voltage between socket 1 of test connection X92 and battery positive terminal (11-14 V).
b) Test for voltage between socket 3 and socket 1 of test connection X92 (0.7-2.5 V).

Impulse Readout Initiation
- Press start button for no less than 2, but no more than 4 seconds.
- Observe and write down indicated impulse readout.
- Press start button again for no less than 2, but no more than 4 seconds.Write down in case further faults are visible. There will be no indication in case no further malfunctions are stored in memory.

CAUTION: Determine all stored malfunction numbers before attempting any further testing or repairs. Disconnecting the CIS-E control unit, battery or overvoltage protection relay will erase all numbers stored in memory.

- Repair observed malfunctions (impulse readout) according to troubleshooting chart. For that purpose, connect socket box according to figure below.

Erasing Malfunctions From Memory
- If a malfunction is corrected without having to disconnect the CIS-E control unit, the impulse readout must be erased from memory as follows:
- With an impulse readout displayed, wait 2 seconds then press the start button for at least 6 seconds.

NOTE: each impulse readout must be erased from memory individually.

- If there is no number displayed, then the stored malfunction is erased from memory.
- If the display shows a number greater than 1, then more system malfunctions are stored in memory.





01 Connector, CIS-E control unit
02 Test cable
03 Multimeter
04 Socket box
N3 CIS-E control unit

Icon Legend For Trouble Shooting Charts:

Impulse Display 1:

Impulse Display 2:

Impulse Display 3:

Impulse Display 4:

Impulse Display 5:

Impulse Display 6:

Impulse Display 7:

Impulse Display 8:

Impulse Display 9:

Impulse Display 10: