Quick answer: The GWM Tank 300 needs a CAN-bus bypass harness, not a universal T-splice. Our Vehicle-Specific Trailer Wiring Harness Kit with Anti-Error CAN Module at $220 USD plugs into the factory tail-light connector — no cutting, no fault codes, warranty-safe fitment for both petrol and PHEV variants.
Which Harness Fits Tank 300?
The GWM Tank 300 requires a CAN-bus bypass trailer wiring harness — a gwm tank 300 trailer wiring harness that taps the factory reserved connector rather than splicing the signal wire is the only safe option for this vehicle.
You have bought a Tank 300, you want to tow a camper trailer, and you search for a harness. The listings split into two camps: universal T-connectors for around $30–$60, and direct-fit plug-and-play kits sitting closer to $175–$330. The price gap feels uncomfortable, but it reflects a real engineering difference on this platform.
The Tank 300's body-on-frame architecture pairs with a modern CAN-bus electrical architecture that monitors load on every circuit. Aftermarket direct-fit harnesses are the most widely referenced option for the GWM Tank 300 Petrol from 10/2022 to current — it uses an OEM-style plug at the factory tail-light connector, no wire cutting required.
Savage Technik also stocks a plug-and-play harness specifically for the Tank 300 Petrol, shipping from Queensland.
We also stock the Vehicle-Specific Trailer Wiring Harness Kit with Anti-Error CAN Module at USD $220 — you leave your year, make, model, and pin type in the checkout note and we supply the correct OEM T-adapter plug matched to your build.
It covers the Tank 300 alongside 25-plus other 4x4 and ute platforms, including Haval H9 and BYD Shark 6, so if you run a mixed fleet it simplifies your inventory.
7-Pin vs 13-Pin: What Do You Need?
For Australian towing, 7-pin flat is the correct socket for the vast majority of camper trailers, box trailers, and caravans — 13-pin ISO 11446 is a European standard that is uncommon on locally registered trailers.
Owners do turn up on Tank 300 Facebook groups asking where to source a 13-pin plug for the Tank 300. That question usually comes from seeing a European-market harness listing. In Australia, your trailer almost certainly terminates in a 7-pin flat SAE-style connector, and that is what most AU-stocked Tank 300 harnesses terminate in as default.
If you are towing a Euro-import caravan with a 13-pin socket on the drawbar, a standard 13-to-7 adapter — available at most trailer accessory shops for under $30 — solves the mismatch without forcing you to rewire the van. Our harness kit is available in EU 13-pin ISO 11446 configuration for certain models if you genuinely need native 13-pin output; specify in your checkout note.
For Tank 300 tow bar wiring in the Australian market, default to 7-pin flat and use an adapter if needed rather than hunting a native 13-pin unit.
Direct-Fit vs Universal: Key Differences
A universal T-splice harness cuts into the vehicle's tail-light wiring; on the Tank 300's CAN-bus system, that load change is detected by the body control module and can trigger a trailer fault warning on the dash.
Owners report two common symptoms from incorrect harness fitment on CAN-bus vehicles: persistent fault codes that refuse to clear, and blinker hyper-flash caused by the module reading an unexpected impedance on the indicator circuit. Neither is a minor annoyance — hyper-flash is an ADR lighting compliance issue and fault codes can disable tow-mode functions.
Direct-fit harnesses work differently. They plug into a factory reserved connector at the tail-light assembly, drawing the trailer signal after the CAN-bus module has already processed it. An anti-error CAN module — included in the kit we stock — regulates the output load to factory specification, preventing short-circuit trips and providing over-current protection.
It also handles fog-light soft start, which eliminates another common fault-code trigger.
The PHEV variant adds a further complication. The Tank 300 PHEV towing mode has attracted reported dealership wiring complaints from owners, with some switching to aftermarket direct-fit solutions after factory harness problems. Any harness you fit to a PHEV should be confirmed compatible with the PHEV-specific loom — check the product listing or contact the supplier before ordering.
The petrol fitment from 10/2022 to current is straightforward; PHEV fitment warrants a direct confirmation call.
Tank 300 Harness Spec Comparison
The table below covers the main direct-fit options commonly referenced for Tank 300 towing electrics in the Australian market as of 2026. Prices in AUD unless noted.
Use this to match your variant and budget before ordering. All options listed use plug-and-play connectors — none require wire cutting as a standard install procedure.
| Product | Connector | CAN Module | Petrol Fit | PHEV Fit | Price (AUD approx.) |
|---|---|---|---|---|---|
| EVparts4x4 Vehicle-Specific Kit | 7-pin flat / 13-pin EU (specify at checkout) | Yes — anti-error, OCP, fog soft-start | 10/2022–current | Confirm at checkout | ~$340 (USD $220) |
| Universal bypass kit | 7-pin flat | Yes — ECU included | 10/2022–current | Petrol-specific; verify for PHEV | ~$175–$220 |
| Savage Technik Plug-and-Play | 7-pin flat | Yes — retains cruise control | Petrol only (confirmed) | Not confirmed | ~$180–$230 |
| OZ Canopies Universal + ECU add-on | 7-pin flat | Yes — ECU sold as add-on | 10/2022–current (with ECU) | Verify with supplier | ~$175 (+ ECU) |
DIY Install: What to Expect
A plug-and-play direct-fit harness on the GWM Tank 300 takes most owners 30 to 60 minutes, requires no cutting or splicing, and can be fully reversed to factory condition.
The factory reserved connector sits behind the tail-light cluster. On the petrol model, access involves removing the trim panel in the boot corner — a trim removal tool and patience get you there without damage. Once the connector is exposed, the harness T-adapter plugs in between the factory plug and the tail-light unit.
A 3 mm bolt-on bracket positions the trailer socket at the towbar. You will need a trim removal tool, gloves, and a handful of zip ties for the cable run. No drilling.
YouTube walkthroughs exist specifically for the Tank 300 harness install — they are worth watching once before you start so you know the routing path. The Vehicle-Specific Trailer Wiring Harness Kit with Anti-Error CAN Module at USD $220 includes installation hardware; the bracket and fixings are in the box.
For broader Tank 300 build-out ideas while you have the trim off, 7 GWM Tank 300 Accessories That Actually Pay Off (2026) covers what else is worth adding at the same time.
If you have the PHEV variant, we recommend having a licensed auto electrician do the install. The PHEV loom runs near high-voltage components and the risk from an incorrect connection is not just a blown fuse — it is a safety issue. That is not a knock on your ability; it is the right call for anyone working near a hybrid system for the first time.
PHEV variant — use a licensed auto electrician: The Tank 300 PHEV loom runs in proximity to high-voltage hybrid components. Incorrect connections on a PHEV carry risks beyond a blown fuse. Book a licensed auto electrician for this variant — it is standard practice, not a sign of difficulty.
Australia Towing Rules to Know
The GWM Tank 300 Petrol has a braked towing capacity of 2,500 kg per GWM Australia specifications — and every kilogram of that capacity relies on your trailer lighting being wired correctly and ADR-compliant.
ADR 62/02 governs trailer lighting output standards in Australia. A harness that causes hyper-flash, missing brake-light signal, or intermittent indicators puts you outside compliance.
In some Australian states, a roadworthiness inspection will fail a tow setup with non-compliant lighting, and insurers have grounds to dispute claims where the trailer electrical connection does not meet ADR standards at the time of an incident.
The petrol Tank 300 carries a payload of 350 kg — notably lower than the diesel variant at 600 kg, which is not available in Australia as of 2026. That payload figure matters when you add a ball weight of 250 kg (the Tank 300's rated figure — check your handbook) plus cargo. Getting the towing electrics right is the legal foundation; getting the weight distribution right is the safety layer on top of it.
A correctly fitted tank 300 7 pin install — using a CAN-bypass harness — satisfies the lighting compliance requirement without touching the factory loom, keeping both your ADR compliance and your GWM warranty intact.
Fitment check
Confirmed compatible with: GWM Tank 300 Petrol 2023–2026 (10/2022 to current), GWM Tank 300 PHEV 2023–2026 (confirm harness compatibility at checkout).
Leave your exact year, make, model, and required pin type in the checkout note when ordering the Vehicle-Specific Kit — we cross-check against factory connector data before dispatch.
FAQ
Does the GWM Tank 300 need a bypass harness or will a universal one do?
The Tank 300 needs a CAN-bus bypass harness — a universal T-splice changes the load on a monitored circuit and typically triggers fault codes or blinker hyper-flash on this vehicle. A direct-fit harness with an anti-error module plugs into the factory reserved connector and avoids both problems. Under Australian Consumer Law, a manufacturer generally cannot void your whole warranty over an accessory unless it directly caused a fault.
Will fitting a trailer wiring harness void my GWM Tank 300 warranty?
A plug-and-play OEM T-adapter harness that uses the factory reserved connector and makes no permanent modifications is the warranty-safe route. Under ACCC provisions, a dealer cannot void your warranty simply for fitting a compatible aftermarket accessory, but cutting or splicing the factory loom gives them grounds to dispute a related claim. The direct-fit harness is fully reversible.
Is the Tank 300 trailer harness compatible with both petrol and PHEV?
The petrol fitment from 10/2022 to current is confirmed compatible. PHEV compatibility depends on the specific harness product — confirm with the supplier before ordering, and have a licensed auto electrician handle the PHEV install due to high-voltage proximity.
Where do I get a 13-pin adapter for my Tank 300 in Australia?
Most trailer accessory retailers and auto parts shops stock a 13-to-7 flat adapter for under $30, which is the practical solution if your caravan has a 13-pin drawbar socket. Alternatively, the Vehicle-Specific Kit from EVparts4x4 can be supplied in EU 13-pin output if you specify at checkout.
Does the trailer wiring harness control electric trailer brakes?
No — the harness powers lighting circuits only: indicators, brake lights, running lights, and reverse. Electric trailer brakes require a separate proportional brake controller, which is a distinct unit and a separate purchase. Never assume a lighting harness alone is sufficient for a braked trailer.
Recommended parts
Proportional Electric Brake Controller
The wiring harness powers trailer lights only — for a caravan or trailer with electric brakes over 2,000kg you also need this.
$338.00
Related reading
Source: GWM Australia specifications
