U0169: Lost Communication With Sun Roof Control Module

What it means

A control module is not receiving expected messages from the Sun Roof Control Module. Sun roof functions may be unavailable; the code alone does not identify why communication was lost.

How it works

The sun roof control module operates the powered roof and communicates its status with other vehicle modules over the network. U0169 sets when a receiving module misses expected messages from the sun roof module in time; the code alone cannot distinguish loss of module power, a CAN wiring fault, or gateway routing trouble.

Common causes

Most likely first.

1. Sunroof module unpowered
2. CAN wiring to sunroof module broken
3. Gateway module routing CAN messages incorrectly

Symptoms

• Powered sun roof functions may be unavailable
• Other communication codes

How to diagnose it

1. Scan all modules and review freeze-frame or event data for other network codes or a low-voltage event.
2. Check whether powered sun roof controls respond and whether the roof is stuck open or closed.
3. Inspect the sun roof module's connectors, power and ground wiring, and CAN wiring for damage, corrosion, looseness, or water entry.
4. Test module power and ground under load against the manufacturer's specification.
5. Check CAN communication at the sun roof module and verify gateway routing using vehicle-specific wiring and diagnostic information.

Common fixes

• Secure or clean a loose or corroded sun roof-module connector.
• Repair damaged power, ground, or CAN wiring to the module.
• Restore a failed module power or ground supply.
• Correct gateway routing if network testing identifies it as the cause.
• Replace the sun roof control module only after its supplies and network circuit test correctly.

Can I keep driving?

If the roof is closed and only its powered functions are affected, driving is generally possible. If it is stuck open, protect the cabin from weather and avoid driving in conditions that could impair visibility or control.