Introduction

HBA diagnosis

Introduction
The manual contains the diagnosis for the following system:
HBA (headlight beam adjustment).

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 decoding and the deleted tuner memory.
- The coding, calibration and headlight adjustment must be observed after an HBA control module or an angle sensor for HBA has been replaced or the running gear has been modified.
- After troubleshooting or repairs, erase the fault memory with the Porsche System Tester 2 and carry out a test drive.
- After the test drive, read out the fault memory with Porsche System Tester 2 again.

CAUTION:
Danger of damage due to improper handling of the battery and the control module connectors.
- Never disconnect battery with engine running.
- Never start engine without securely connected battery.
- Never pull off or push on plug connections of 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.:
- Power failure
- Plug connections disconnected

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.

1.Open circuit/short to ground/short to B+:
Open circuit / short to ground:
There is (present) or was (not present) a short circuit to ground or an open circuit in the circuit to the control module terminal.

Short to B+:
There is (present) or was (not present) a short circuit to voltage.

2. Version / vehicle parameters
Incorrect vehicle coding or coding not carried out.

3. Counter
When a fault first occurs, a fault entry is made in the fault memory and the memory is simultaneously set to 50. If a fault is present, the counter is incremented by 1 each time the ignition is switched on. The maximum count is 100. The counter is decremented if the fault is no longer present. The fault memory is erased automatically when the counter reaches 0.