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Jeep U0109

Inspect the harness routing at the seat mounting location as seen below. Repair any pinched harness conditions using

DriveNot yet established by verified evidence.
ChargeNot yet established by verified evidence.
ServiceService inspection is appropriate, particularly when U0109 or the listed warnings occur after second-row seat removal.
Confidence95%

Quick answer

For certain 2022–2023 Jeep Grand Cherokee vehicles in the US, DTC U0109 may occur after a repair requiring second-row seat removal. Verified NHTSA manufacturer communication evidence directs inspection of harness routing at the seat mounting location for pinched harness conditions.

This page separates verified manufacturer/regulator evidence from supporting material. Unsupported causes, repairs or safety conclusions are not guessed.

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1. What does U0109 mean?

For certain 2022–2023 Jeep Grand Cherokee vehicles in the US, DTC U0109 may occur after a repair requiring second-row seat removal. Verified NHTSA manufacturer communication evidence directs inspection of harness routing at the seat mounting location for pinched harness conditions.

2. Technical explanation

U0109 is identified in the supplied official manufacturer communication as “Lost Communication with the Fuel Pump Control Module.” The communication states that this code, along with air-suspension, evaporative-system, or PHEV-related concerns involving the Power Inverter Module (PIM) or power electronic coolant pumps, may be observed after recent removal of the second-row seat. The documented inspection focus is harness routing at the seat mounting location.

3. What system is affected?

Fuel Pump Control Module communication. The same verified communication also references possible air-suspension, evaporative-system, PHEV PIM, and power-electronic coolant-pump concerns in the stated scenario.

4. How serious is this code?

Not yet established by verified evidence.

5. Symptoms you may notice

  • Malfunction Indicator Lamp (MIL) may be on.
  • A Service Air Suspension warning message may be displayed.
  • Evaporative-emission-system faults may be present.
  • On a PHEV, concerns associated with the Power Inverter Module (PIM) or power electronic coolant pumps may be present.
  • The concerns may occur after a recent repair involving removal of the second-row seat.

6. Possible causes

  • Pinched harness conditions at the seat mounting location are identified by the official manufacturer communication as the inspection target.
  • Other causes are not yet established by verified evidence.

7. Can I still drive the vehicle?

Not yet established by verified evidence.

8. Can I charge the vehicle?

Not yet established by verified evidence.

9. What you can safely do

  • If this code or the listed warnings occur after second-row seat removal, arrange professional inspection of the harness routing at the seat mounting location.
  • Avoid attempting high-voltage system repair or modification.

10. Step-by-step troubleshooting

  1. Confirm whether the vehicle recently underwent a repair involving removal of the second-row seat.
  2. Have a qualified service technician inspect harness routing at the seat mounting location for pinching, as directed in the official communication.
  3. Have any identified pinched harness condition repaired according to applicable manufacturer procedures.

11. When to contact service

Service inspection is appropriate, particularly when U0109 or the listed warnings occur after second-row seat removal.

12. What the service center may check

  • Inspect harness routing at the seat mounting location.
  • Check for pinched harness conditions.
  • Assess the condition in relation to recent second-row seat removal.

13. Possible repair or resolution

  • Repair any pinched harness condition using applicable manufacturer procedures. The specific repair method is not fully established by the supplied verified evidence.

14. Affected vehicles

15. Related TSBs / service bulletins

  • NHTSA Manufacturer Communication PDF 10242736: S2308000082, published July 8, 2023. It addresses MIL illumination, Service Air Suspension messages, evaporative-emission faults, and certain PHEV PIM or power-electronic coolant-pump concerns that may follow second-row seat removal.

16. Recall information

No recall relationship is established by verified evidence.

17. Official manufacturer information

Verified source: NHTSA Manufacturer Communication PDF 10242736: S2308000082. https://static.nhtsa.gov/odi/tsbs/2023/MC-10242736-9999.pdf

19. Frequently asked questions

What does U0109 mean in this documented Jeep scenario?

The supplied official communication identifies U0109 as Lost Communication with the Fuel Pump Control Module.

What should be inspected after second-row seat removal?

The official communication directs inspection of harness routing at the seat mounting location for pinched harness conditions.

Does this apply to every Jeep vehicle?

The supplied applicability evidence is limited to US-market 2022–2023 Jeep Grand Cherokee vehicles.

Is it safe to drive or charge?

Not yet established by verified evidence.

20. Sources & verification

ReferenceVerified
Jeep U0109: Inspect the harness routing at the seat mounting location… | EV Diagnostics