300SL (129.061) L6-3.0L (104.981) (1991)
Data Link Connector: Description and Operation
On-Board Diagnostic Connector
California Models
On-Board Diagnostic Connector Terminal Designations
The on-board diagnostic connector with push-button and light emitting diode (LED) is located on the engine compartment firewall. The on-board
diagnostic connector provides information concerning fault conditions within the CIS-E(5), SRS, EZL/AKR, MAS, Electronic A/T transmission and
other computer controlled systems. Up to 34 fault codes concerning emission related problems may be accessed with the incorporated push-button and
"LED", however, an impulse counter or the Bosch ON/OFF Ratio tester must be used for trouble code access of other related engine systems.
When the push-button is depressed for 2 to 4 seconds (ignition ON), the LED will begin a blink impulse readout. The cause(s) of the malfunction will be
indicated by the number of blink impulses. Upon completion of the blink impulse readout, the LED remains on (does not blink). By pressing the
push-button again for 2 to 4 seconds, an additional malfunction blink impulse will begin (if present). If no further malfunctions are stored in the fault
memory the first fault code will reappear.
Federal Models
On-Board Diagnostic Connector Terminal Designations
The on-board diagnostic connector provides information concerning fault conditions within the CIS-E(5), SRS, EZL/AKR, MAS, Electronic A/T
transmission and other computer controlled systems. Up to 34 fault codes concerning CIS-E(5) related problems may be accessed with the use of an
impulse counter. Furthermore, 15 additional (MAS) control unit fault codes concerning engine operation may also be extracted at the on-board
diagnostic connector.