Checking wiring of diagnostic sockets — AUDI

Notes:

Use hand-held multimeter V.A.G 1526 A, adapter set V.A.G 1594 A and test box V.A.G 1598 A for test
Switch off ignition before checking wiring.

Testing power supply for "black" diagnostic socket

Installation position of diagnostic sockets: in additional relay carrier I

=> "Current flow diagrams, Electrical fault finding and fitting locations" binder

Contact assignment for "black" diagnostic socket:

1 -
Earth
2 -
Terminal 30

Select measuring range on hand-held multimeter V.A.G 1526: Voltage measurement (20 V=)
Contact / Diagnosis socket · Measure to · Testing of · Specification · Action in event of deviation from specified value
1 1) · Battery positive · Wiring to / car body earth point · Approx. battery voltage · - Check wiring using current flow diagram
2 1) · Car body earth point · Wiring to continuous positive (terminal 30) · Approx. battery voltage · - Check wiring using current flow diagram

1)
Earth connection and power supply for black diagnostic socket => Fig., Page
01-144
.

Testing wiring between "white" diagnostic socket and magnetic clutch control unit -J153 and operating and display unit -E87, respectively

Installation position of diagnostic sockets and of cable junction K: in additional relay carrier I

=> "Current flow diagrams, Electrical fault finding and fitting locations" binder

Contact assignment for "white" diagnostic socket:

1 -
L-line (is not required here)
2 -
K-line

Note:

Wiring between "white" diagnostic socket (contact 2) and gearbox control unit runs through junction K:

=> "Current flow diagrams, Electrical fault finding and fitting locations" binder

If fully automatic air conditioner is fitted, remove operating and display unit -E87 => Fig.
87-98
and connect test box V.A.G 1598 A with adapter cable V.A.G 1598/11.

Magnetic clutch control unit - J153

Select measuring range on hand-held multimeter V.A.G 1526: Resistance measurement (20 kω) / ▪ Adapter cable V.A.G 1598/11 connected.
Control unit -J153 · Testing of · ▪ Test conditions / - Additional operations · Specification · Action in event of deviation from specified value
Pin D + K 1) / Pin D + 2 2) · Wiring · ▪ Ignition switched off · Less than 1.5 ω · - Check wiring using current flow diagram
Pin D + / car body earth point · ∞ ω · - Measures in the event of short circuit => Page 01-148

Operating and display unit -E87

Select measuring range on hand-held multimeter V.A.G 1526: Resistance measurement (20 kω) / ▪ Adapter cable V.A.G 1598/11 connected.
V.A.G 1598 A Socket · Testing of · ▪ Test conditions / - Additional operations · Specification · Action in event of deviation from specified value
41 + K 1) / 41 + 2 2) · Wiring · ▪ Ignition switched off · Less than 1.5 ω · - Check wiring using current flow diagram
41 + / car body earth point · ∞ ω · - Measures in the event of short circuit => Page 01-148

1)
Corresponding contact at auxiliary relay carrier I => Fig., Page
01-146
.

2)
Corresponding contact at "white" diagnostic socket => Fig., Page
01-146
.

Testing cable connection of white diagnostic socket for short circuit to positive or to earth

Note:

This check has to be performed if one of the following displays appears on connected fault reader V.A.G 1551.

Rapid data transfer
Communication fault
Indicated on display:

or

Rapid data transfer
HELP
K-line not switching to earth

or

Rapid data transfer
HELP
K-line not switching to positive

Control unit does not answer!
HELP
When indicated on display:

Open circuit in wiring to magnetic clutch control unit -J153 and operating and display unit -E87, respectively.

Note:

Switch off ignition before unplugging wiring.

Switch off ignition.

Unplug all wiring connections of other vehicle systems with self-diagnosis "Rapid data transfer" one after the other from junction K.

=> "Current flow diagrams, Electrical fault finding and fitting locations" binder

After each wiring connection to a vehicle system has been disconnected, switch on ignition or run engine at idling speed, respectively, and once again enter address word 08 for "AC/heating electronics" => Page
01-36
.
If control unit identification and coding then appears in display, check wiring to control unit which was last disconnected according to current flow diagram
If no fault in wiring is found, replace control unit last disconnected, if necessary, and re-connect all wiring to junction K.