U0616 — Lost Communication With Engine Coolant Bypass Valve B

What Does U0616 Mean?

U0616 is a diagnostic trouble code indicating: Lost Communication With Engine Coolant Bypass Valve B. This code relates to the vehicle systems system. The vehicle's computer detected a condition outside normal operating parameters and stored this code.

Symptoms of U0616

⚠️ Check Engine Light (MIL) illuminated
⚠️ No communication with Engine Coolant Bypass Valve B
⚠️ Multiple warning lights may illuminate simultaneously
⚠️ Related system completely inoperative
⚠️ System warning light illuminated

Common Causes

🔍 CAN bus wiring fault (open or shorted) to Engine Coolant Bypass Valve B
🔍 Power or ground supply issue to Engine Coolant Bypass Valve B
🔍 Engine Coolant Bypass Valve B internal failure
🔍 Water intrusion damaging module or connectors
🔍 CAN bus termination resistor fault

Frequently Asked Questions

What does U0616 mean?

U0616 indicates: Lost Communication With Engine Coolant Bypass Valve B. The vehicle's computer has detected that the Engine Coolant Bypass Valve B is not operating within its expected parameters and stored this diagnostic trouble code.

Can I drive with code U0616?

You can drive short distances for essential trips, but schedule a diagnosis soon. Driving with U0616 for extended periods may cause additional problems.

How much does it cost to fix U0616?

Repair costs for U0616 typically range from $80 to $800, depending on the root cause. Simple wiring or connector repairs are on the lower end, while component replacement costs more. A proper diagnosis ($80–$150 at most shops) will identify the exact cause before committing to expensive parts.

What To Do Next

Possible Fixes

🔧 Inspect CAN bus wiring to Engine Coolant Bypass Valve B for damage
🔧 Check power and ground supply to Engine Coolant Bypass Valve B
🔧 Replace failed Engine Coolant Bypass Valve B

1
Find your vehicle above
Click your make and model for real owner reports and common causes specific to your vehicle.
2
Check for recalls
Go to nhtsa.gov/recalls and enter your VIN. Free repairs if covered.
3
Get a professional diagnosis
A code alone doesn't identify the exact failed part. A diagnostic ($50–$150) pinpoints the root cause.

U0616: Lost Communication With Engine Coolant Bypass Valve B