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16502ModerateEngine

16502 on 1996-2001 Audi A4 — Engine Coolant Temperature Sensor (G62): Signal too High

1 vehicles · 1 makes · $30-$180 repair

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Most Reported On

1996-2001Audi A4

16502 is an OBD-II diagnostic trouble code meaning “Engine Coolant Temperature Sensor (G62): Signal too High.” VAG/VCDS fault code 16502 corresponds to OBD-II code P0118 (Ross-Tech address 000280). It indicates the engine control module detected an abnormally high voltage signal from the Engine Coolant Temperature (ECT) sensor G62. High voltage is read as an implausibly cold engine (often colder than ambient), typically caused by an open circuit or failed sensor, and can disrupt cold-start fueling, idle, and the cooling-fan/warm-up strategy. This code is most commonly reported on 1996-2001 Audi A4, with repair costs ranging from $30 to $180.

On This Page

  • Common Causes
  • Repair Cost
  • Vehicles (1)
  • Related Codes
  • FAQ
  • Sources (2)
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Common Causes

1Faulty engine coolant temperature sensor (G62) reading out of range
2Open or broken wiring in the ECT sensor signal circuit
3Corroded, loose, or damaged sensor connector / poor ground
4Loss of ground reference to the sensor
5Low coolant level or air in the cooling system affecting the sensor
6Failed or faulty engine control module (rare)

Typical Repair Cost

$30 - $180

Based on 1 documented vehicle-specific issues. Actual cost depends on root cause and vehicle.

Diagnostic Tools

To diagnose 16502, you'll need an OBD-II scanner. Here are our recommendations at every price point.

Budget Pick$10–$20

ANCEL AD310 Classic OBD-II Scanner

by ANCEL

A simple, affordable code reader that reads and clears check engine codes. Great for quick diagnostics on any OBD-II vehicle (1996+).

  • Read & clear engine codes
  • View freeze frame data
  • I/M readiness status
  • No batteries or app needed
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Best Value$90–$120

BlueDriver Pro Bluetooth Scanner

by BlueDriver

Bluetooth OBD-II scanner with a free companion app. Provides enhanced diagnostics, smog readiness, and repair reports sourced from a database of verified fixes.

  • Enhanced diagnostics (ABS, SRS, transmission)
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  • Smog check readiness
  • Free app (iOS & Android)
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Advanced$180–$230

LAUNCH CRP123X OBD-II Scanner

by LAUNCH

A professional-grade handheld scanner that reads all four major systems (engine, transmission, ABS, SRS) with live data streaming and graphing.

  • Engine, transmission, ABS, SRS diagnostics
  • Live data stream & graphing
  • AutoVIN for vehicle identification
  • Free lifetime updates via Wi-Fi
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Professional$350–$450

Autel MaxiCOM MK808S Diagnostic Tool

by Autel

Shop-level diagnostic tablet with bi-directional control, active tests, and full system coverage. Ideal for serious DIYers and small shops.

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  • Oil reset, EPB, BMS, TPMS, injector coding
  • 7-inch touchscreen with Android OS
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Vehicles Affected (1)

Audi 16502 page →
A4Moderate

G62 Engine Coolant Temperature Sensor (black-housing) fails causing erratic temp gauge, hard cold starts and rich-running

1996-2001$30-$1800 reports

Related Codes (8)

16500Engine Coolant Temp. Sensor (G62): Implausible Signal002FManufacturer-Specific Diagnostic Code00522Engine Coolant Temperature Sensor (G62): Open Circuit / Short to Positive (B+)16566Mass Air Flow Sensor Signal Too Low (VAG)17664Engine Coolant Temperature Circuit (G62): Open / Short to B+ECM-940AEngine Control Module Fault (Volvo)P0008Engine Position System Performance - Bank 1P0009Engine Position System Performance - Bank 2

FAQ

What does 16502 mean?

16502 stands for "Engine Coolant Temperature Sensor (G62): Signal too High." VAG/VCDS fault code 16502 corresponds to OBD-II code P0118 (Ross-Tech address 000280). It indicates the engine control module detected an abnormally high voltage signal from the Engine Coolant Temperature (ECT) sensor G62. High voltage is read as an implausibly cold engine (often colder than ambient), typically caused by an open circuit or failed sensor, and can disrupt cold-start fueling, idle, and the cooling-fan/warm-up strategy.

What are the most common causes of 16502?

The most common causes of 16502 are: Faulty engine coolant temperature sensor (G62) reading out of range, Open or broken wiring in the ECT sensor signal circuit, Corroded, loose, or damaged sensor connector / poor ground, Loss of ground reference to the sensor, Low coolant level or air in the cooling system affecting the sensor, Failed or faulty engine control module (rare). The specific cause varies by vehicle.

How much does it cost to fix 16502?

Repair costs for 16502 range from $30 to $180, depending on the vehicle and root cause.

Which vehicles are affected by 16502?

Au7o has documented 16502 across 1 vehicle models from 1 manufacturers: Audi.

Sources (2)

  • ForumGuide on how to replace a G62 Coolant Temperature Sensor - Audifans.net
  • ForumCoolant Sensor, Updated Green, G62 (ELTH-OEM) - JH Motorsports
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Content compiled with AI assistance using NHTSA complaints, TSBs, and owner reports. May contain errors. Always verify with your vehicle's service manual.

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