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Connecting Tester Or Scanner, Reading and Erasing DTC Memory




NOTE: Observe all system specific instructions listed in the "Preparation for Test" section of each Test Program.

Diagnostic trouble codes (DTC's) which have been stored due to testing or the disconnection of lines must be erased from the diagnostic trouble code memory at the end of testing.

Special Tools:





Connect Hand-Held Tester (HHT) according to connection diagram.
The following functions can be performed according to the instructions on the display:
a) Reading/erasing DTC memory
b) Reading actual values
c) Performing activations
d) Programming control modules


Special Tools:





Connect Impulse Counter Scan Tool (according to connection diagram).
LED "U-Batt" must light up in the display.
If LED does not light up, check:
a) Voltage supply.
b) Impulse counter scan tool fuse.

NOTE: DTC readout is no longer possible using the impulse counter scan tool, with some systems, please review DTC memory in each system section prior to starting the DTC readout for the system being checked.

1. Read Diagnostic Trouble Code Memory with Impulse Counter
a) Ignition: ON
b) Press start button for 2 to 4 seconds.
c) Read and record diagnostic trouble code (DTC).
d) Press start button again for 2 to 4 seconds.
e) Read and record DTC.
Repeat steps d) and e) until the first DTC reappears

2. Clear Diagnostic Trouble Code Memory with Impulse Counter 1)
a) Press start button for 2 to 4 seconds (DTC appears)
b) Wait 3 seconds, then press start button for 6 to 8 seconds, thereby erasing the previously displayed DTC from memory.
c) Each stored DTC must be erased individually.

1) Erasing of stored diagnostic trouble codes must begin within 20 seconds of reading the DTC. After 20 seconds, the DTC can no longer be erased. Erasing procedure can be restarted by performing DTC memory readout after the fault is again displayed.


38-pole Data Link Connector (X11/4)


Connection Diagram:





013 Impulse counter scan tool
075 Adaptor for impulse counter scan tool
087 Hand-Held Tester (HHT)
094 Multiplexer 965 589 00 40
X11/4 Data link connector

Connect impulse counter scan tool as follows:
Red wire (circuit 30, voltage): socket 3
Black wire (circuit 31, ground): socket 1
Yellow wire to diagnostic output socket of the system being tested.


Connection Diagram:





087 Hand-Held Tester (HHT)
094 Multiplexer, 965 589 00 40
X11/4 Data link connector

Adapter cable, 965 589 00 50 00 (not shown)

Connect HHT as follows:
1. Connect HHT with Multiplexer (094) attached to Data link connector X11/4
2. Turn Ignition: ON
3. According to instructions in HHT display:
a) Readout DTC memory/erase
b) Readout Actual values
c) Perform Activations
d) Program control modules
4. Disconnect HHT.

CAUTION: Observe all system specific instructions listed in the "Preparation for Test" section of each Test Program.

Diagnostic trouble codes (DTC's) which have been stored due to testing or the disconnection of lines must be erased from the diagnostic trouble code memory at the end of testing.