C0550 — Vacuum Sensor B Circuit High

Q: "Can I drive with this code?"

"It depends on the severity. If the vehicle runs normally, short trips are usually OK. If you notice performance issues, drivability problems, or warning lights beyond the check engine light, get it checked soon."

Q: "Will this code clear itself?"

"Some codes clear automatically after the underlying issue is fixed and several drive cycles pass. But the root cause must be addressed first."

Q: "How do I find the exact cause?"

"A code alone doesn't pinpoint the failed part. You need a diagnostic scan ($50-150 at most shops) that reads freeze frame data and live sensor readings to identify the specific component."

What Does C0550 Mean?

C0550 is a diagnostic trouble code indicating: Vacuum Sensor B Circuit High. This code relates to the chassis system. It has been reported in NHTSA complaints across 1 different vehicle models.

Symptoms of C0550

⚠️ Check engine light illuminated
⚠️ Steering issues

Common Causes

🔍 Wiring or connector problem
🔍 Sensor or control module malfunction

C0550 Reports by Year

2019

1

2014

1

Real Owner Reports

From NHTSA complaint database — actual owner descriptions.

"SUDDEN FAILURE OF POWER STEERING WHILE DRIVING. GM DEALERSHIP RAN DIAGNOSTIC TEST. DIAGNOSIS IS STEERING ASSIST MOTOR IS SHORTING INTERNALLY AND SHUTTING DOWN THE ASSIST. OCCASIONALLY, THE COMPUTER WILL SUCCESSFULLY RESET AND POWER STEERING WILL BE RESTORED FOR A SHORT WHILE UNTIL IT HAPPENS AGAIN. "
— Chevrolet Malibu owner, 08/09/2019

"LOSS OF STEERING CONTROL WHILE DRIVING ON EXPRESSWAY AT 50+MPH. DIFFICULT TO MAINTAIN CONTROL. ABLE TO SLOW DOWN AND EXIT FREEWAY. DEALER WAS CLOSE BY SO LEFT ON LOT OVERNIGHT. CHECK ENGINE LIGHT ALSO HAD COME ON. DEALER REPORTED FOUND CODE C0550 WHEN RUNNING DIAGNOSTICS. DEALER INFORMED THE P/"
— Chevrolet Malibu owner, 12/23/2014

Source: NHTSA Complaints Database

Most Reported Vehicles for C0550

Based on NHTSA owner complaint data.

#	Vehicle	Reports
1	CHEVROLET MALIBU

C0550 Reports by Vehicle

Detailed NHTSA complaint analysis for each vehicle model.

CHEVROLET MALIBU

2 NHTSA reports · Peak: 2006

Frequently Asked Questions

Can I drive with this code?

It depends on the severity. If the vehicle runs normally, short trips are usually OK. If you notice performance issues, drivability problems, or warning lights beyond the check engine light, get it checked soon.

Will this code clear itself?

Some codes clear automatically after the underlying issue is fixed and several drive cycles pass. But the root cause must be addressed first.

How do I find the exact cause?

A code alone doesn't pinpoint the failed part. You need a diagnostic scan ($50-150 at most shops) that reads freeze frame data and live sensor readings to identify the specific component.

What To Do Next

Possible Fixes

🔧 Have the code scanned with a professional-grade scanner to read freeze frame data
🔧 Test the relevant sensor(s) with a multimeter before replacing
🔧 Inspect wiring harness and connectors for damage, corrosion, or loose connections
🔧 If DIY repair isn't feasible, get a diagnostic from a trusted mechanic ($50-150)

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.

C0550: Vacuum Sensor B Circuit High