AutoCodes – Cadillac – P1018 Cadillac

P1018 Cadillac Code - Reductant Control Module Sensor Communication Voltage Supply Circuit Low Voltage

Quick Answer

The Reductant Quality Sensor is located in the reductant tank and uses an ultrasonic signal to measure reductant fluid quality. Common causes include Faulty Reductant Control Module, Reductant Control Module harness is open or shorted, Reductant Control Module 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: P1018 Cadillac indicates Reductant Control Module Sensor Communication Voltage Supply Circuit Low Voltage.
Common causes: Common causes include Faulty Reductant Control Module, Reductant Control Module harness is open or shorted, Reductant Control Module 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 407

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 24, 2021

Description
Possible Causes
How To Fix
Cost to Diagnose
FAQs
Comments
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Code P1018 Cadillac Description

The Reductant Quality Sensor is located in the reductant tank and uses an ultrasonic signal to measure reductant fluid quality. The Reductant Quality Sensor includes an integrated temperature sensor to measure reductant fluid temperature. The Reductant Quality Sensor communicates with the Reductant Control Module using serial data. The Diagnostic Trouble Code (DTC) will be set if the reductant control module detects a short to ground on the 5 V reference circuit for greater than 1 s.

OBDII Code P1018 Cadillac - Reductant Control Module Sensor Communication Voltage Supply Circuit Low Voltage - AutoCodes.com — P1018 Cadillac Code - Reductant Control Module Sensor Communication Voltage Supply Circuit Low Voltage

What does this mean?

What are the Possible Causes of the DTC P1018 Cadillac?

Faulty Reductant Control Module
Reductant Control Module harness is open or shorted
Reductant Control Module circuit poor electrical connection
Faulty Reductant Quality Sensor

How to Fix the DTC P1018 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 P1018 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.

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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.

Frequently Asked Questions about P1018 Cadillac Code

1. What are the common symptoms of OBDII code P1018 in a Cadillac?

- Common symptoms include poor engine performance, reduced fuel efficiency, and the illumination of the check engine light.

2. What does the OBDII code P1018 in a Cadillac indicate?

- This code indicates a low voltage supply circuit issue related to the Reductant Control Module Sensor communication.

3. What are the possible causes of the low voltage supply circuit issue in a Cadillac triggering code P1018?

- Possible causes include a faulty Reductant Control Module Sensor, damaged wiring or connectors, or issues with the voltage supply to the sensor.

4. How can I diagnose the OBDII code P1018 in my Cadillac?

- Diagnosis involves using an OBDII scanner to retrieve the code, inspecting the Reductant Control Module Sensor and its connections, and testing the voltage supply circuit for abnormalities.

5. Can I continue driving my Cadillac with OBDII code P1018?

- It is not recommended to continue driving with this code present, as it can lead to further engine issues and potential damage if left unaddressed.

6. Are there any DIY repair tips for fixing the low voltage supply circuit issue causing OBDII code P1018 in a Cadillac?

- DIY repair tips include checking and cleaning the sensor connections, inspecting for damaged wiring, and ensuring a stable voltage supply to the sensor.

7. Is it necessary to replace the Reductant Control Module Sensor when dealing with OBDII code P1018 in a Cadillac?

- In some cases, replacing the sensor may be necessary if it is found to be faulty or damaged during diagnosis.

8. How much can I expect to pay for repairing OBDII code P1018 in a Cadillac at a professional auto repair shop?

- Repair costs can vary depending on the exact cause of the issue, but you can expect to pay anywhere from $200 to $500 for parts and labor.

9. Will resetting the check engine light clear OBDII code P1018 in my Cadillac?

- Resetting the check engine light may temporarily clear the code, but it will return if the underlying issue causing the low voltage supply circuit problem is not addressed.

10. How can I prevent OBDII code P1018 from recurring in my Cadillac in the future?

- Regularly inspecting and maintaining the Reductant Control Module Sensor, ensuring proper wiring connections, and addressing any voltage supply issues promptly can help prevent the code from recurring.