AutoCodes – Generic – P1620

P1620 Code - Low Engine Coolant Circuit Conditions

Quick Answer

With the engine running, the Powertrain Control Module (PCM) detects that the Engine Coolant Switch signal was low (indicating an open circuit) for 20 seconds Common causes include Faulty Engine Coolant Switch, Engine Coolant Switch harness is open or shorted, Engine Coolant Switch 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: P1620 indicates Low Engine Coolant Circuit Conditions.
Common causes: Common causes include Faulty Engine Coolant Switch, Engine Coolant Switch harness is open or shorted, Engine Coolant Switch 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 41,079

How popular is this code, among other codes? Medium

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 01, 2019

Description
Possible Causes
How To Fix
Cost to Diagnose
FAQs
Comments
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Code P1620 Description

With the engine running, the Powertrain Control Module (PCM) detects that the Engine Coolant Switch signal was low (indicating an open circuit) for 20 seconds

OBDII Code P1620 - Low Engine Coolant Circuit Conditions - AutoCodes.com — P1620 Code - Low Engine Coolant Circuit Conditions

What does this mean?

What are the Possible Causes of the DTC P1620?

Faulty Engine Coolant Switch
Engine Coolant Switch harness is open or shorted
Engine Coolant Switch circuit poor electrical connection

How to Fix the DTC P1620?

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 P1620 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 P1620 code?

Need more information on how to fix the P1620 code? Get Access to Factory Service Manuals

Need Help with the Code?

Get the P1620 code diagnosed by a professional: Find a repair shop in your area

Information for Specific Makes

P1620 Audi — Instrument Panel Engine Coolant Temperature Signal Open Circuit / Short To Positive
P1620 BMW — Map Cooling Thermostat Control Circuit Signal High
P1620 Buick — Low Engine Coolant Circuit Conditions
P1620 Cadillac — Low Engine Coolant Circuit Conditions
P1620 Chevrolet — Low Engine Coolant Circuit Conditions
P1620 GMC — Low Engine Coolant Circuit Conditions
P1620 Hyundai — A/C Relay Malfunction
P1620 MINI — Map Cooling Thermostat Control Circuit Signal High
P1620 Volkswagen — Instrument Panel Engine Coolant Temperature Signal Open Circuit / Short To Positive
P1620 Volvo — MIL Requested By Throttle Unit

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 P1620 Code

1. What are common symptoms of OBDII code P1620 (Low Engine Coolant Circuit Conditions)?

- Common symptoms include engine overheating, low coolant levels, and potential engine misfires.

2. What are the possible causes of OBDII code P1620?

- Causes can include a faulty coolant temperature sensor, a malfunctioning thermostat, a coolant leak, or a problem with the cooling system.

3. How can I diagnose the issue related to OBDII code P1620?

- Diagnose by checking coolant levels, inspecting for leaks, testing the coolant temperature sensor, and examining the thermostat for proper operation.

4. What are the potential risks of ignoring OBDII code P1620?

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

5. Can I continue driving with OBDII code P1620 active?

- It is not recommended to continue driving with this code active, as it can lead to potential engine damage and safety hazards.

6. How can I repair OBDII code P1620?

- Repair options may include replacing the coolant temperature sensor, fixing coolant leaks, replacing the thermostat, and ensuring the cooling system is functioning properly.

7. Will resetting the OBDII code P1620 resolve the issue?

- Resetting the code may temporarily clear the warning light, but it will not fix the underlying issue causing the code to appear.

8. Is it possible for a DIY enthusiast to fix OBDII code P1620?

- Yes, some repairs related to this code can be done by DIY enthusiasts, such as checking coolant levels and replacing the coolant temperature sensor.

9. How long does it typically take to repair OBDII code P1620?

- The repair time can vary depending on the specific cause of the issue, but it may take anywhere from a few hours to a full day to complete the necessary repairs.

10. Can a mechanic help diagnose and repair OBDII code P1620?

- Yes, a qualified mechanic can diagnose the issue using specialized tools and expertise, as well as perform the necessary repairs to fix OBDII code P1620.