P0AD4: Hybrid/EV Battery Pack Air Flow System Insufficient Air Flow

P0AD4 is a system-level check of air-cooled traction batteries: the controller concludes that too little air passes the cells, for example because the cell temperatures rise faster than the commanded fan level allows, as a Honda fan diagnosis patent describes. CARB 1968.2 asks for a functional check of the battery cooling performance where feasible. Stellantis lists P0AD4 for the 48 V eTorque battery of the Ram 1500 (TSBs 08-033/034/035-24, 2022-24) and cures some cases with a battery pack control module software update. Unlike the fan circuit codes, P0AD4 is often caused by a blocked intake or duct. Expect a warning lamp and limited assist or electric power.

High severity. Can I keep driving?If the car still runs, drive as little as possible and go to a specialized repair shop. Do not touch the orange cables: they carry high voltage.

Symptoms

Check engine or hybrid warning light
Reduced electric assist or start-stop not available
Battery fan runs loud for long periods

Most likely causes

Cabin air intake grille or duct of the battery blocked (bags, clothing, dust, pet hair)
Battery air filter clogged, where fitted
Battery fan running too slowly
Battery controller software sets the code falsely (Ram eTorque, fixed by update)

What to check, in order

Start with the simplest. You can tick off each step.

Read the codes with a hybrid-compatible scanner and write down the freeze frame data
Make sure the battery cooling air intake is clean
Check the 12 V auxiliary battery, which can also trigger warnings
Leave any high-voltage measurements to a specialized repair shop

Good to know

Repair difficulty: easy
It can trigger limp mode.
It affects emissions.

What each character of P0AD4 means

P: Powertrain: engine and transmission
0: Generic code: same on every make
A: Hybrid or air and fuel
D4: Specific fault in that system

Frequently asked questions

Can I keep driving with code P0AD4?

If the car still runs, drive as little as possible and go to a specialized repair shop. Do not touch the orange cables: they carry high voltage.

What causes code P0AD4?

The most common causes are: cabin air intake grille or duct of the battery blocked (bags, clothing, dust, pet hair); battery air filter clogged, where fitted; battery fan running too slowly.

Related codes

Sources

Values and procedures vary by manufacturer. If it affects brakes, steering, fuel or high voltage, see a professional. Updated: 2026-11-04. How we build these pages.