AutoCodes – Cadillac – P1203 Cadillac

P1203 Cadillac Code - Gas Mass Sensor Circuit High Frequency

Quick Answer

P1203 Cadillac indicates Gas Mass Sensor Circuit High Frequency. Common causes include Faulty Gas Mass Sensor, Gas Mass Sensor harness is open or shorted, Gas Mass Sensor 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: P1203 Cadillac indicates Gas Mass Sensor Circuit High Frequency.
Common causes: Common causes include Faulty Gas Mass Sensor, Gas Mass Sensor harness is open or shorted, Gas Mass Sensor 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.

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Code Popularity 2,931

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 Jul 11, 2019

Description
Possible Causes
How To Fix
Cost to Diagnose
Comments
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Code P1203 Cadillac Description

OBDII Code P1203 Cadillac - Gas Mass Sensor Circuit High Frequency - AutoCodes.com — P1203 Cadillac Code - Gas Mass Sensor Circuit High Frequency

What does this mean?

What are the Possible Causes of the DTC P1203 Cadillac?

Faulty Gas Mass Sensor
Gas Mass Sensor harness is open or shorted
Gas Mass Sensor circuit poor electrical connection

How to Fix the DTC P1203 Cadillac?

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 P1203 Cadillac 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 P1203 Cadillac code?

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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.