AutoCodes – Pontiac – P1641 Pontiac

P1641 Pontiac Code - Cooling Fan Relay 1 Control Circuit

Quick Answer

Ignition voltage is supplied to the Cooling Fan relay coil. Common causes include Faulty Cooling Fan Relay, Cooling Fan Relay harness is open or shorted, Cooling Fan Relay circuit poor electrical component. 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: P1641 Pontiac indicates Cooling Fan Relay 1 Control Circuit.
Common causes: Common causes include Faulty Cooling Fan Relay, Cooling Fan Relay harness is open or shorted, Cooling Fan Relay circuit poor electrical component.
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 6,645

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 04, 2019

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

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

Code P1641 Pontiac Description

Ignition voltage is supplied to the Cooling Fan relay coil. The Powertrain Control Module (PCM) controls the relay by grounding the control circuit via an internal switch called a driver. The primary function of the driver is to supply the ground for the component being controlled. Each driver has a fault line which is monitored by the PCM. When the PCM is commanding a component ON, the voltage of the control circuit should be low (near 0 volts). When the PCM is commanding the control circuit to a component OFF, the voltage potential of the circuit should be high (near battery voltage). If the fault detection circuit senses a voltage other than what is expected, the fault line status will change causing the code to set.
The relay is used to control the high current flow to the cooling fan motors. This allows the PCM driver to only have to handle the relatively low current used by the relay.

OBDII Code P1641 Pontiac - Cooling Fan Relay 1 Control Circuit - AutoCodes.com — P1641 Pontiac Code - Cooling Fan Relay 1 Control Circuit

What does this mean?

What are the Possible Causes of the DTC P1641 Pontiac?

Faulty Cooling Fan Relay
Cooling Fan Relay harness is open or shorted
Cooling Fan Relay circuit poor electrical component

How to Fix the DTC P1641 Pontiac?

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 P1641 Pontiac 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 P1641 Pontiac code?

Need more information on how to fix the P1641 Pontiac code? Get Access to Factory Service Manuals

Need Help with the Code?

Get the P1641 Pontiac 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.

Frequently Asked Questions about P1641 Pontiac Code

1. What are the common symptoms of OBDII code P1641 in a Pontiac related to the Cooling Fan Relay 1 Control Circuit?

- Common symptoms include overheating of the engine, the cooling fan not turning on when needed, and potential issues with the vehicle's air conditioning system.

2. What are the possible causes of OBDII code P1641 in a Pontiac?

- The code P1641 can be triggered by a faulty cooling fan relay, a damaged relay control circuit, a malfunctioning cooling fan motor, or a problem with the engine coolant temperature sensor.

3. How can I diagnose the Cooling Fan Relay 1 Control Circuit issue in my Pontiac?

- You can start by checking the cooling fan fuse, relay, and wiring connections. Using a multimeter, you can test the relay and the control circuit to determine if they are functioning properly.

4. Can I drive my Pontiac with OBDII code P1641 present?

- It is not recommended to drive your Pontiac with code P1641 as it can lead to engine overheating and potential damage. It's best to address the issue promptly to avoid further complications.

5. How do I repair OBDII code P1641 in my Pontiac related to the Cooling Fan Relay 1 Control Circuit?

- Repairing the issue may involve replacing the cooling fan relay, repairing or replacing damaged wiring, fixing the cooling fan motor, or addressing any issues with the coolant temperature sensor.

6. Are there any DIY tips for fixing OBDII code P1641 in a Pontiac?

- DIY tips include checking and cleaning the cooling fan relay connections, inspecting the wiring for any visible damage, and ensuring the cooling fan motor is running smoothly.

7. What are the potential risks of ignoring OBDII code P1641 in a Pontiac?

- Ignoring code P1641 can lead to engine overheating, which may cause severe damage to the engine components and result in costly repairs.

8. Can a faulty engine coolant temperature sensor trigger OBDII code P1641 in a Pontiac?

- Yes, a malfunctioning engine coolant temperature sensor can send incorrect signals to the PCM, resulting in the triggering of code P1641 related to the Cooling Fan Relay 1 Control Circuit.

9. How long does it typically take to repair OBDII code P1641 in a Pontiac?

- The repair time can vary depending on the exact cause of the issue. Simple fixes like replacing the cooling fan relay may take less than an hour, while more complex repairs could require several hours.

10. Is it necessary to reset the OBDII system after repairing code P1641 in a Pontiac?

- Yes, it is recommended to clear the OBDII system after fixing the issue to ensure the code is no longer present and to monitor if the problem has been successfully resolved.