If your 300C won't start
Get safe first
On the road, get everyone somewhere safe, away from the traffic, with your hazard lights on. Call roadside assistance if you have it. If anyone's hurt or in danger, call 000.
Find the jump-start terminals
The manual says remote terminals in the engine compartment are there for jump-starting, so you shouldn't need the boot for this. Follow the jump-starting steps in your own manual.
Get the battery tested
One jump doesn't prove the battery is bad. Have it tested, along with the alternator, before you buy a new one. Our car battery page covers what a good test includes.
Where is the battery in a Chrysler 300C?
The 300 SRT manual we read says: "The battery is stored under an access cover in the trunk." A copy of a 2014 Chrysler 300 manual reads differently, placing it between the left headlight and the left front wheel splash shield. Both are American books, so go by the manual in your glovebox.
Wherever it sits, leave the fitting to the mechanic, who can check the charging system while they're there.
When it isn't the battery
CarsGuide answered a 2009 300C owner in 2025 about random, grouped electrical faults. It pointed to the TIPM, the unit that combines the car's fuses, relays and control electronics, and suggested trying a known-good one, disconnecting the battery overnight, and looking for a bad earth.
So if your 300C has odd electrical gremlins along with a flat battery, say so. It can stop you paying for a battery that was never the problem. Diagnostics explains how that fault-finding works.
Which 300C do you have?
The first generation (model years 2005 to 2010) came as a sedan or wagon, and the second as a sedan only. The 5.7-litre Hemi V8 has a Multi-Displacement System that can drop to four cylinders when less power's needed. A mechanic who knows Hemis will know to ask about it.
Diesels differ by generation: a 3.0-litre Mercedes-Benz sourced V6 on the first, and a 3.0-litre VM Motori V6 turbodiesel later. Those want a mechanic who does diesel work. The SRT8 had a 6.1-litre Hemi and its own needs.
Servicing a Chrysler now the brand has left
The Chrysler marque was withdrawn from the Australian market on 19 November 2021, after right-hand-drive production ended that year. Your 300C, Voyager, PT Cruiser or Crossfire still runs on the schedule in its owner's manual, so that's where to start.
If you've got a late car with warranty left, servicing by a qualified independent mechanic, to Chrysler's schedule and specifications, doesn't by itself void it. For repair work, the consumer law says it must be done with due care and skill, whoever does it.
Parts are the question to raise early. Ask the mechanic if they can get what your car needs before the job starts, and how long that takes.
What kind of mechanic suits a Chrysler
One with American V8 time, or Mercedes and VM diesel time if that's your car, and the gear to read Chrysler fault codes. Tell us the model, the year and the engine. A local mechanic who specialises in your car.
What you can do on your 300C
You can
- Read the battery and jump-starting pages of your owner's manual.
- Note what stopped working, and in what order, if the faults are electrical.
- Check the oil level and tyre pressures before the first drive of the day.
Leave to the mechanic
- Battery and alternator testing, and fitting the battery.
- TIPM and wiring diagnosis.
- Diesel fuel system and engine work.
What we'd do with a flat 300C
We'd jump it from the engine bay terminals, then get the battery and charging system tested before buying anything. If there's a run of strange electrical faults as well, we'd ask the mechanic to look past the battery first. Once it's sorted, we'd check the service history against the manual, and ask about parts before anything's pulled apart.