Parts for your 2017 Holden Commodore-Alternator

2017 Holden Commodore alternator — what it does and how to look after it

Based on technical references including the Holden VF/VF II Commodore Service Manual (Charging System), GM Service Information (Generator/Charging Description and Operation) and the Holden Genuine Parts catalogue for MY17 VF models, the 2017 Holden Commodore is fitted with an engine-driven alternator (often called the generator in OEM docs). Both the 3.6‑litre V6 and 6.2‑litre V8 variants use a smart‑controlled alternator to maintain the 12‑volt system and battery.

The alternator’s job is straightforward: keep the battery charged and power everything electrical once the engine’s running. On the 2017 Commodore, it’s an electronically regulated, ECU‑managed unit that adjusts output to suit load and driving conditions, helping fuel economy and battery life. Expect charging voltage at the battery to sit roughly between 13.5 and 14.8 volts depending on temperature, load and state of charge.

As part of regular servicing, the alternator deserves a quick health check. Under the bonnet, a technician will inspect the drive belt and tensioner, look for pulley wobble, listen for bearing whine, and check the main B+ cable and earths for corrosion or looseness. A simple charging test with the headlights, demister and A/C on will confirm the alternator can hold voltage under load. Because smart charging relies on battery condition, testing the battery at the same time is a must, a weak battery can make a good alternator look bad.

Replacement is straightforward for a trained tech: disconnect the negative terminal, relieve belt tension, unplug the control connector and B+ cable, then remove the mounting bolts. Refitting involves correct belt routing and tension, proper torque on the fasteners, and a final charging system test. Most workshops in Australia and New Zealand will quote around 1–2 hours labour, varying with engine and options. Choosing a quality new or premium remanufactured unit is wise, it saves headaches with noise, low output or dash warnings.

For everyday care, it’s smart to:

• Have the charging system and battery tested annually or before winter
• Replace cracked or glazed belts and noisy tensioners promptly
• Keep terminals clean and tight to avoid voltage drop and warning lights

Look after the alternator and the Commodore’s electrics stay happy—no flat batteries, no dim lights, and no surprise warning lamps on the dash.

Popular questions about the 2017 Holden Commodore alternator

What are common signs the alternator is failing?
Owners often notice a battery/charging light, dimming headlights at idle, slow or repeated flat batteries, electrical glitches, or a whining/grinding noise from the alternator pulley area. If jump-starts are becoming a habit, it’s time for a proper charging and battery test.

What voltage should it charge at?
With the engine running, a healthy system typically shows about 13.5–14.8 V at the battery. The ECU’s smart charging can vary voltage with load and temperature, so brief dips or rises can be normal. Consistently under 13.2 V or over 15.0 V under normal conditions warrants inspection.

How long does replacement take and what else should be changed?
Most workshops allow 1–2 hours. It’s sensible to assess the serpentine belt and tensioner at the same time and replace them if worn. After fitting, a battery test and a quick scan for charging-related fault codes ensure everything’s behaving.