Telephone/Telematics - Introduction

PCM2/CDR23
(Telephone)

91-D 121 Telephone/telematics - Introduction
The manual contains the diagnosis for the following system:
PCM2

General instructions/safety instructions
The following points must be observed during vehicle diagnosis:
- After the battery is connected, volatile memories must be reprogrammed. In the case of radio coding and tuning, the customer must be informed of the decoding and the deleted tuner memory.
- After the battery has been connected, the instructions in the assembly must be observed.
- Deactivate the "automatic traffic announcement" before beginning the diagnosis on the PCM2. If this is not done, the system will crash.
- When working on the optical waveguide, please observe the instructions in assembly Optical waveguide - MOST bus.
- After troubleshooting or repairs, erase the fault memory with the Porsche System Tester II No. 9588 and carry out a test drive.
- After the test drive, read out the fault memory with the Porsche System Tester II No. 9588 again.

DANGER:
Danger of injury through triggering of driver's airbag
- Never hang the Porsche System Tester II No. 9588 over the steering wheel.

CAUTION:
Danger of damage due to improper handling of the battery and the control unit connectors'.
- Never disconnect battery with engine running.
- Never start engine without securely connected battery.
- Never pull off or push on plug connections for the control modules or other electronic components when the ignition is switched on.

General information on the fault memory

Fault code setting conditions

Fault codes can be set in several circumstances, e.g.:
- battery disconnected
- plug connections disconnected
- power failure

In these circumstances, no fault is present in the system and the fault memory must be erased.

Fault memory Info key [F8]
In order to be able to assess the fault exactly, the fault memory Info key [F8] must be pressed. This information should be saved using the Save key [F4] and printed out. If a fault code is stored with "not present" status and no other problems are present, then the fault memory must be erased.

Open circuit - short to ground / voltage short / version; vehicle parameters / counter

Frequency counter
First occurrence -vehicle network voltage
First occurrence - operating hours