Can a bad battery cause P0600?

Yes. Low or unstable voltage disrupts CAN communication. Check battery voltage and grounds before assuming a module has failed.

Will clearing the code fix it?

No. Clearing codes is not a repair. The communication fault is still there and will return immediately.

How serious is this compared to other engine codes?

It is one of the more serious codes because it can affect every system on the vehicle simultaneously. Get it diagnosed promptly.

Codes › P0600

P0600: The engine computer has a communication network fault

Serial Communication Link Malfunction

SevereCan you keep driving?

Do not drive if you are experiencing other symptoms like no-start, misfires, or warning lights across multiple systems. Bring it to a shop by tow if necessary.

What it means

Modern vehicles have multiple computers talking to each other over a CAN bus network. P0600 means there is a fault in that communication link. This is a broad code that does not identify which module has stopped communicating or why. It can accompany dozens of other codes. The practical meaning is that one or more modules are not able to share data reliably. Wiring integrity to the CAN bus, battery voltage, and corroded ground connections are the most common physical causes. A jump-start with dead batteries is a known trigger on some platforms.

Common causes

Damaged or shorted CAN bus wiringThe two CAN bus wires can short together or to ground, disrupting all module communication.
Corroded or loose battery connections and ground strapsLow or unstable voltage disrupts CAN communication. Check ground straps to chassis and engine.
Failed module pulling the bus downOne defective module can bring down communication for all others on the same bus.
PCM or TCM failureThe primary controller itself has failed. Requires professional diagnosis to confirm.

What it costs

Battery and grounds inspection and repair$50 to $200
CAN bus wiring repair$200 to $600
Module replacement (varies by which module)$300 to $2,000 or more

Symptoms

Multiple warning lights across different systems
Erratic instrument cluster readings
Transmission shift problems
Engine performance issues
Non-responsive controls

What to do next

This code requires a scan tool that can read CAN network activity, not just generic OBD codes. Bring it to a shop with factory-level diagnostic capability. Before paying for module replacement, have the technician verify battery voltage, all ground connections, and CAN bus wire integrity. Module replacements are expensive and often require programming.

Lewis captures the full list of codes stored across all available modules at the time of the scan, which helps a technician quickly identify which module dropped off the network. Download Lewis.

Related codes

FAQ

Can a bad battery cause P0600?: Yes. Low or unstable voltage disrupts CAN communication. Check battery voltage and grounds before assuming a module has failed.
Will clearing the code fix it?: No. Clearing codes is not a repair. The communication fault is still there and will return immediately.
How serious is this compared to other engine codes?: It is one of the more serious codes because it can affect every system on the vehicle simultaneously. Get it diagnosed promptly.