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Alfa Romeo 145/146 Electrical System Diagnosis Manual, Volume 3 (1994-2001)02 · 146 electrical system diagnosis
02 · Diagnostics

FUNCTIOnAL DESCRIPTION (TD, TD-CAT version)

Make
Alfa Romeo
Model
145/146 Electrical System Diagnosis Manual, Volume 3
Year
1994–2001
Section
Power Supply › FUNCTIOnAL DESCRIPTION (TD, TD-CAT version)
146 electrical system diagnosisFUNCTIOnAL DESCRIPTION (TD, TD-CAT version)

FUNCTIOnAL DESCRIPTION (TD, TD-CAT version)

The supply leading from the battery A1 is subdivided into the various lines in the branch terminal box G56, from which the numerous cables that directly supply certain systems (protected by specific "wander" fuses) and the line that supplies the fusebox G1 lead; inside the fusebox, the supply is sorted to the various circuits, protected by the corresponding fuses (see the "Fusebox" section).

The battery charging line leads directly from the alternator A3 or (from chassis no. ....) via the branch terminal box G56.

The ignition switch B1 is also supplied through the branch terminal box G56 at pin B of connector B.

The line leaving pin A of connector B is the one corresponding to the "START" position and directly supplies the starter motor A11 (only for certain cars without ALFA ROMEO CODE but with theft alarm, through the alarm control unit N45 and the starting consensus relay I10).

The line that leaves pin 3 of connector A - "DRIVE" position - via the fusebox G1, supplies the "key-operated" circuits, which are however disengaged in the "START" position.

The lines that leave pin 1 of connector A and pin C of connector B supply the "key-operated" circuits which remain engaged also when the ignition key is turned to "START", either directly or via the fusebox G1.

Lastly, the line that leaves pin 2 of connector A corresponds to the "PARK" position and supplies the side-lights circuit inside the fusebox G1.

From chassis no....., through the adoption of a special high capacity fuse (150A) G393, all the supply lines are protected with the exception of the starter motor cable (battery - starter motor) and the battery charging cable (starter motor - alternator) which are protected by an additional "reinforced" sheath.

A fuse G384 (50A) has also been added to protect the supply for the ignition switch.

COMPONENTS AND CONNECTORS (TD, TD-CAT version)

Battery A1
35RED • A11 4RED • G125b 4RED • G125b
10RED • G56 10RED • A3 6RED • G254
16RED-BLK • G393 10BLK • G53b 35BLK • G318
35BLK • G318 35BLK • G318
Alternator, with built-in voltage regulator A3 Starter motor A11
10RED • A1 B+ 35RED • A1 30
10RED • G56 (•)

(•) Variant from chassis no....

Battery, alternator, starter motor wiring diagram for TD-TD-CAT version

Parts & tools for this job For 1994 Alfa Romeo 145/146

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