[SOLVED] Fix U1291 Code: Relay Control Module Communication Lost

The automobile fault code U1291 indicates a problem with the Relay Control Module or Rear Multiplex Integrated Control Unit (MICU). The most common symptom is the Engine Light ON or Service Engine Soon Warning Light. The cause of this fault code could be a faulty Relay Control Module, open or shorted harness, poor electrical connection, or a faulty Rear Multiplex Integrated Control Unit (MICU).

The repair importance is high as it can affect the vehicle’s performance and fuel efficiency. The repair difficulty is moderate, and the repair time is estimated at 1.0 hour.

To fix the issue, one should visually inspect the related wiring harness and connectors, check for damaged components, and look for broken, bent, pushed out, or corroded connector’s pins.

Repair Importance Level10.0 (Out of 10)
Estimated Repair TimeApproximately 1.0 hour
Repair Difficulty Level10.0 (Out of 10)

If you notice the Engine Light ON (or Service Engine Soon Warning Light), it could be due to the u1291 fault code. Here are the symptoms to look out for:

  • The automobile fault code U1291 has the following symptoms: Engine Light ON, Service Engine Soon Warning Light ON.

The automobile fault code U1291 can be caused by a faulty relay control module, open or shorted harness, poor electrical connection, or a faulty rear MICU.

  • The automobile fault code U1291 can be caused by a faulty Relay Control Module.
  • It can also be caused by an open or shorted Relay Control Module harness.
  • Another possible cause is a poor electrical connection in the Relay Control Module circuit.
  • Lastly, a faulty Rear Multiplex Integrated Control Unit (MICU) can also trigger the U1291 fault code.

To fix the u1291 automobile fault code, check the possible causes and inspect related wiring harness, connectors, and components for damage.

  • To fix the automobile fault code u1291, you need to check the possible causes listed above.
  • Visually inspect the related wiring harness and connectors.
  • Look for damaged components and check for broken, bent, pushed out, or corroded connector’s pins.
  • This fix will take an estimated repair time of 1.0 hour.

The automobile fault code U1291 has an estimated repair time of 1.0 hour. The cost of fixing this code varies depending on the auto repair shop, with most charging between $75 and $150 per hour.

These factors can influence the overall cost of diagnosis and fixing.

The u1291 fault code is a communication malfunction between the Relay Control Module and the Rear Multiplex Integrated Control Unit (MICU). This code indicates that the MICU has lost communication with the Relay Control Module.

When this fault code appears, it means that there is a problem with the communication system between these two modules, which can cause issues with the vehicle’s electrical system.

It is important to have this issue diagnosed and repaired as soon as possible to prevent further damage to the vehicle.

What are the possible causes of the u1291 automobile fault code?

If you’re experiencing the u1291 fault code, your engine light may be on. This could be due to a faulty Relay Control Module, an open or shorted harness, poor electrical connection in the circuit, or a faulty Rear Multiplex Integrated Control Unit (MICU). To fix the issue, check the possible causes listed above, visually inspect the wiring harness and connectors, and look for any damaged components or corroded pins.

How can one visually inspect the related wiring harness and connectors to fix the u1291 fault code?

If you’re experiencing the u1291 fault code, which is indicated by the engine light being on or the service engine soon warning light, there are a few possible causes. These include a faulty relay control module, an open or shorted harness, poor electrical connection in the circuit, or a faulty rear multiplex integrated control unit (MICU). To fix the issue, start by visually inspecting the related wiring harness and connectors. Look for any damaged components and check for broken, bent, pushed out, or corroded connector pins.

What are the signs that the Relay Control Module harness is open or shorted in the u1291 fault code?

If you see the Engine Light ON or Service Engine Soon Warning Light, it could be a sign of a faulty Relay Control Module or a Relay Control Module harness that is open or shorted. Other possible causes include a Relay Control Module circuit with poor electrical connection or a faulty Rear Multiplex Integrated Control Unit (MICU). To fix the issue, check the possible causes listed above and visually inspect the related wiring harness and connectors. Look for damaged components and check for broken, bent, pushed out, or corroded connector’s pins.

u1291 error fault code explained

If you see the Engine Light ON or Service Engine Soon Warning Light, it could be due to a faulty Relay Control Module, Relay Control Module harness, Relay Control Module circuit poor electrical connection, or a faulty Rear Multiplex Integrated Control Unit (MICU).

Check the possible causes, inspect the wiring harness and connectors, and look for damaged components or corroded connector pins.

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