Lost Communication With Four-Wheel Drive Clutch Control Module
What it means
Another module has stopped receiving messages from the four-wheel-drive clutch control module over the CAN bus. This module controls the electronic clutch that sends part of the torque to the second axle in all-wheel-drive systems, and when communication is lost the vehicle usually runs in two-wheel drive only. The cause is usually module power, a connector exposed to water and mud under the vehicle, or the bus wiring, and several U codes together point to a bus or power problem.
Symptoms4
- Four-wheel or all-wheel-drive warning light on.
- Vehicle runs in two-wheel drive only, with less traction on sand or slippery roads.
- Stability or traction control light on in some vehicles.
- Scan tool cannot communicate with the four-wheel-drive clutch module.
Possible causes6
- Module connector or wiring corroded by water or mud under the vehicle.
- Blown module power fuse.
- Poor module ground.
- Weak battery or loose terminals.
- Open or shorted bus wiring, especially at chafe points under the vehicle.
- Internal module failure.
How to diagnose5
- Read codes from all modules; if many modules report lost communication, start with the battery and the bus, and if only the four-wheel drive clutch control module is missing, focus on it.
- Try to communicate with the four-wheel drive clutch control module directly with a scan tool; no response points to lost power, ground or wiring to it.
- Locate the four-wheel drive clutch control module from the manufacturer information, which exists on four-wheel or all-wheel-drive vehicles that send torque through an electronic clutch, often near the rear axle or transfer case, depending on the make, then check its power fuse and measure power and ground at its connector.
- Inspect the module connector for water, corrosion or loose terminals, and check the bus wiring to it.
- Disconnect the battery and measure resistance between the CAN bus wires at the module connector, comparing with the manufacturer specification to find an open or short.
How to fix6
- Charge or replace the battery, and clean and tighten its terminals.
- Replace the blown fuse after finding why it blew.
- Clean the module connector and repair the ground or damaged bus wiring.
- Update the module software if the manufacturer has an update.
- Replace the four-wheel drive clutch control module if proven faulty with good power and bus wiring, then program and code it to the vehicle.
- Clear codes in all modules and confirm the code does not return.
Repair cost
In Saudi riyals; the highlighted part is the expected range for this fault.
The cost is low for a fuse or corroded connector, rises with underbody wiring repairs, and is highest if the module must be replaced and programmed.
Prices are rough estimates for common cars at independent workshops and vary with the car and the source of the part.
Prices last updated: September 2026
Frequently asked questions
Can I drive with this code?
Yes, with caution on normal roads, but the vehicle usually runs in two-wheel drive only, so avoid sand, off-road and slippery roads until it is fixed.
How is this code different from U0102?
U0102 concerns the transfer case module on traditional four-wheel-drive vehicles, while this code concerns the electronic clutch module in all-wheel-drive systems. Which one exists depends on the vehicle.
Why does it appear after desert trips?
The module or its wiring sits near the underside of the vehicle, where water, mud and chafing can corrode connectors or damage wires.
This guide is for information only and does not replace an inspection by a qualified technician. If the fault involves brakes, steering, engine temperature, electrics or refrigerant, do not attempt the repair yourself.
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