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P0691ModeratePowertrain

P0691 on 2021-2023 Jeep Grand Wagoneer — Fan 1 Control Circuit Low

1 vehicles · 1 makes · $450-$1,600 repair

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Most Reported On

2021-2023Jeep Grand Wagoneer

P0691 is an OBD-II diagnostic trouble code meaning “Fan 1 Control Circuit Low.” This code means the engine computer detected low voltage (or a short to ground) in the control circuit for cooling fan 1. The PCM commands the cooling fan via a relay or control circuit and monitors the signal voltage. A fault can prevent the fan from running properly, risking engine overheating in traffic or at low speeds. This code is most commonly reported on 2021-2023 Jeep Grand Wagoneer, with repair costs ranging from $450 to $1,600.

On This Page

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

1Faulty cooling fan relay
2Failed cooling fan motor
3Short to ground in the fan control wiring
4Corroded or damaged fan connector
5Blown fan fuse
6PCM fan-control driver fault

Typical Repair Cost

$450 - $1,600

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

Diagnostic Tools

This is a powertrain code, so a basic OBD-II reader can read it. These read P0691.

Reads P codes$20–$40

ANCEL AD310 Classic OBD-II Scanner

by ANCEL

A simple code reader for engine (P) codes on many compatible OBD-II vehicles. It does not support every vehicle or hybrid/EV application, and it does NOT read body, chassis or network codes; confirm exact-vehicle compatibility before buying.

  • ✓Read & clear engine (P) codes
  • ✓View freeze frame data
  • ✓I/M readiness status
  • ✓No batteries or app needed
Check Price on Amazon
Reads P codes$90–$120

BlueDriver Pro Bluetooth Scanner

by BlueDriver

Bluetooth scanner with a companion app that reads beyond the engine module — ABS, SRS and transmission — plus manufacturer-specific codes on many vehicles.

  • ✓Enhanced diagnostics (ABS, SRS, transmission)
  • ✓Repair Reports with verified fixes
  • ✓Smog check readiness
  • ✓Free app (iOS & Android)
Check Price on Amazon
Reads P codes$180–$230

LAUNCH CRP123X V3.0 Elite OBD-II Scanner

by LAUNCH

Handheld scanner covering the 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
Check Price on Amazon
Reads P codes$350–$450

Autel MaxiCOM MK808S Diagnostic Tool

by Autel

Shop-level tablet with all-system coverage and bi-directional control, so you can command a module rather than only read it.

  • ✓All-system diagnostics (25+ modules)
  • ✓Bi-directional control & active tests
  • ✓Oil reset, EPB, BMS, TPMS, injector coding
  • ✓7-inch touchscreen with Android OS
Check Price on Amazon

What you can do yourself, and what needs a shop

Reading the code, clearing it, and watching whether it returns is a driveway job with the right scanner. These steps are not:

  • •Module programming or software updates — needs the manufacturer software or a J2534 pass-through with a paid subscription.
  • •Replacing a control module — most are VIN-programmed and immobilizer-registered, so a new one does nothing until it is coded to your car.
  • •Airbag/SRS component work — a stored fault can deploy a live device.

If the vehicle is still under warranty, check for an open recall or technical service bulletin before buying anything — the repair may already be covered.

As an Amazon Associate, we earn from qualifying purchases. Prices are approximate and may vary.

Vehicles Affected (1)

Jeep P0691 page →
Grand WagoneerCritical

Cooling Fan Module Failure / Overheating Warning

2021-2023$450-$1,60058 owner reports

Related Codes (8)

P0690ECM/PCM Power Relay Sense Circuit HighP0692Fan 1 Control Circuit HighP0693Cooling Fan 2 Control Circuit LowP0694Cooling Fan 2 Control Circuit HighP0013"B" Camshaft Position Actuator Circuit/Open (Bank 1)P0020Camshaft Position 'A' Actuator Circuit (Bank 2)P0023"B" Camshaft Position Actuator Circuit/Open (Bank 2)P0025"B" Camshaft Position - Timing Over-Retarded (Bank 2)

FAQ

What does P0691 mean?

P0691 stands for "Fan 1 Control Circuit Low." This code means the engine computer detected low voltage (or a short to ground) in the control circuit for cooling fan 1. The PCM commands the cooling fan via a relay or control circuit and monitors the signal voltage. A fault can prevent the fan from running properly, risking engine overheating in traffic or at low speeds.

What are the most common causes of P0691?

The most common causes of P0691 are: Faulty cooling fan relay, Failed cooling fan motor, Short to ground in the fan control wiring, Corroded or damaged fan connector, Blown fan fuse, PCM fan-control driver fault. The specific cause varies by vehicle.

How much does it cost to fix P0691?

Repair costs for P0691 range from $450 to $1,600, depending on the vehicle and root cause.

Which vehicles are affected by P0691?

Au7o has documented P0691 across 1 vehicle models from 1 manufacturers: Jeep.

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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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