P2689 - OBD Trouble Code

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The trouble code P2689 can be elucidated as Fuel Supply Heater Control Circuit High. This code would indicate that an issue has been detected in the fuel supply heater control circuit.

This trouble code is generic, which would mean that it can apply to all the vehicles which are equipped with the OBD-II or the vehicles which are made since 1996 up to the present. The specifications on the definition, the troubleshooting steps as well as repairs can always vary from one vehicle make to another. The fuel supply heater control circuit is being monitored by the engine control module. This trouble code would be set by the ECM when the fuel supply heater control circuit would not be as per the specifications set by the manufacturer.

What causes this problem with the Fuel Supply Heater Control Circuit High?

• Malfunctioning fuel supply heater
• Fuel supply heater harness might be unlocked
• Fuel supply heater circuit might have bad electrical connection

1. Engine Control Module - Dead cells in batteries can cause a failure in the engine control module. Many times a battery is left in the rig long after a cell has died. This would affect the grounding in the car battery.
2. Powertrain Control Module - If there are some faults in the PCM, then it may throw off the timing and fuel settings of the engine, which can negatively affect the performance. A flawed PCM may cause the vehicle to experience a reduction in fuel efficiency, power as well as acceleration.
3. Engine Wiring Harness - The broken wires in the wiring harness might lead to some serious engine problems. So make sure that you replace your faulty engine wiring harness to avoid such situation.
4. Electronic Control Unit - Do you know that the poor performance or unexplained drops in fuel economy or efficiency are often associated to onboard car computer problems, or defective ECU issues?
5. Fuel Delivery System Parts - If you want your car engine to run perfectly, then you will need an efficient fuel system for that. The parts of fuel system are fuel tank, filter, pump, tank and injector or carburetor. If there is a failure in any of these components, then it would lead to faults in the entire fuel system. We have top notch fuel delivery system parts for our dear customers.
6. Diagnostic Tools - Use factory grade diagnostic tools to resolve OBD code P2689 error. Buy new diagnostic tools and equipment for us.

You might be thinking that how would you diagnose these problems? We at Parts Avatar Canada would help you diagnose the major symptoms easily.

Common Symptoms

• Visibility in the check engine light

Looking out for some ways with the help of which you can correct this fault code? Then you have arrived at the correct place. We are here to help you out, so you must check out the steps mentioned below as follows:

• Repair or replace the quirky PCM
• Recondition the non-functioning fuel supply heater circuit
• It is necessary to perform proper service of the unsound fuel supply heater
• Make sure to mend the faulty electronic control unit
• Adjust the flawed fuel supply heater harness

There is no need to get strained if your OBD Code is still flashing up as we are here at your service. Have a look at our superior variety of PCM, fuel supply heater, electrical connectors, ecm car, ecu car, pcm car, body control module component, powertrain control module, electronic control module, pcm module, ecm module, exhaust sensor, ECM and many more. Now all your problems would vanish within no time.

Here are some steps which you should follow in order to diagnose this fault code:

• The P2689 fault code is related to the fuel supply heater control circuit. The powertrain control module controls the electronic fuel supply heater. Fuel supply heater systems are used primarily in geographic areas with extremely low temperature situations. When this particular type of code is presented, it would indicate that a malfunction has taken place in the CAN. CAN stands for “controller area network.” The CAN represents a communication bus that would allow a number of microcontrollers to communicate with one another without the need for a host computer.
• It is a message based protocol initially designed for automotive use. The network of CAN bus is actually a complex conglomeration of wiring harnesses and connectors used as a pipeline of information which is shared between two or more automotive control modules. Every electrical function of the vehicle is virtually controlled by these controllers, with the powertrain control module being the primary controller. Control modules receive input data from various sensors and emit output signals to system constituents and other control modules.
• If this proves to be a CAN bus associated situation, then it could prove very challenging to diagnose by an amateur technician. Unlike other diagnostic codes, this type of code can sometimes be best left to a professional simply because of the bulk of circuitry involved. An technician which is experienced should use a specialized scanner (Autohex or Tech II) to determine the general area of the malfunction much more rapidly and easily than someone using a code reader as well as a digital volt ohmmeter.
• If you will disconnect and check every single pin of the CAN bus then it can consume a lot of time as well as money. Also make sure to install some type of memory saving device, test the PCM and other controllers lose their memory and sometimes they might require reprogramming. A specialized diagnostic CAN scanner will depict pin values and control module operation without risking a meltdown. It can diagnose computer and issues related to circuitry correctly by monitoring automobile operation while the vehicle is being operated. If you want to diagnose this type of code using a digital volt ohmmeter, then it would entail probing thousands of circuits separately. One probe which is misplaced could destroy expensive control modules and require that the vehicle be totally reprogrammed.
• At the most, you may attempt to perform a continuity test after all control modules are disconnected, and this could literally require 40-hours or more, based upon the automobile. There are some applications are equipped with up to 18 separate control modules. If you choose to tackle this monumental task, then you must start with a careful visual inspection of all system circuitry, connectors, and fuses.
• Control module ground circuits should be inspected for continuity with battery ground. Generally the faulty system grounds are reason behind the occurrence of these types of codes. An auxiliary ground cable can be supportive in diagnosing system ground discrepancies. Engine and transmission ground cables, straps, and wires are sometimes left dangling once the repairs have been made. Search for loose or corroded electrical connectors that might rise the circuit resistance and cause these types of codes to be stored.
• Obtain a CAN bus system wiring diagram and/or pin out value chart, then use the digital volt ohmmeter to test continuity between individual controller connectors. You must compare your findings with the manufacturer’s referenced values and repair open or shorted circuits as per the need. It is more economical to restore the faulty wiring rather than attempting to remove it from the complex web of wiring harnesses.

Common Mistakes When Diagnosing The P2689 Code

• Fuel supply heater relay might start failing
• Defective powertrain control module
• Some issues related to the fuel supply heater
• Issues with the car wiring