AutoCodes – Buick – P1661 Buick

P1661 Buick Code - MIL Control Circuit Conditions

Quick Answer

With the engine speed over 600 rpm, the Powertrain Control Module (PCM) detects that the Actual and Commanded state of the MIL Control circuit did not match, condition met for over 5 seconds. Common causes include Faulty Malfunction Indicator Lamp (MIL), Malfunction Indicator Lamp (MIL) harness is open or shorted, Malfunction Indicator Lamp (MIL) circuit poor electrical connection. Severity is High - diagnose this code as soon as possible. Driving is not recommended if the warning light is flashing, the engine runs poorly, or safety-related symptoms are present.

What it means: P1661 Buick indicates MIL Control Circuit Conditions.
Common causes: Common causes include Faulty Malfunction Indicator Lamp (MIL), Malfunction Indicator Lamp (MIL) harness is open or shorted, Malfunction Indicator Lamp (MIL) circuit poor electrical connection.
Severity: High - diagnose this code as soon as possible.
Can I drive?: Driving is not recommended if the warning light is flashing, the engine runs poorly, or safety-related symptoms are present.

Save to My Repairs My Repairs

AI answers can be wrong. Verify repairs with testing. Open full chat

Code Popularity 4,572

How popular is this code, among other codes? Low

Repair Importance Level

Urgent (Diagnose now) (3 / 3)

Repair Difficulty Level

Advanced (Pro) (3 / 3)

What is this?

Table of contents Created and updated by William Orellana on Sep 06, 2019

Description
Possible Causes
How To Fix
Cost to Diagnose
Comments
Add Comment

💬 Need more help? Ask Coddy for instant answers — it's free!

Code P1661 Buick Description

With the engine speed over 600 rpm, the Powertrain Control Module (PCM) detects that the Actual and Commanded state of the MIL Control circuit did not match, condition met for over 5 seconds.

OBDII Code P1661 Buick - MIL Control Circuit Conditions - AutoCodes.com — P1661 Buick Code - MIL Control Circuit Conditions

What does this mean?

What are the Possible Causes of the DTC P1661 Buick?

Faulty Malfunction Indicator Lamp (MIL)
Malfunction Indicator Lamp (MIL) harness is open or shorted
Malfunction Indicator Lamp (MIL) circuit poor electrical connection

How to Fix the DTC P1661 Buick?

Review the 'Possible Causes' above and visually examine the corresponding wiring harness and connectors. Check for damaged components and inspect connector pins for signs of being broken, bent, pushed out, or corroded.

What is the Cost to Diagnose the Code?

Labor: 1.0

To diagnose the P1661 Buick code, it typically requires 1.0 hour of labor. Rates vary by location, vehicle, and shop. Many shops charge between $80–$150 per hour; dealerships and metro areas may be higher, independents may be lower.

Need more information about the P1661 Buick code?

Need more information on how to fix the P1661 Buick code? Get Access to Factory Service Manuals

Need Help with the Code?

Get the P1661 Buick code diagnosed by a professional: Find a repair shop in your area

About the author: William Orellana is a Master Mechanic and Mechanical Engineer with over 30 years of experience diagnosing and repairing vehicles. Learn more about his background.