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Chrysler U1124-00

Use wiTech to verify the HV coolant heater status. The Electric Coolant Heater (ECH) status can be found under the HCP > DATA folder (example below). OFF o ECH operation is normal,

Common search variants: U112400 · U1124 00 · U1124_00 · Search ignores case and common separators.

DriveNot yet established by verified evidence.
ChargeNot yet established by verified evidence.
ServiceService evaluation is appropriate because the verified procedure calls for wiTECH status verification and diagnostics of low-voltage, high-voltage, cooling-system, and ground conditions. Service urgency is not yet established by verified evidence.
Confidence95%

Quick answer

For certain 2021–2022 Chrysler Pacifica vehicles in the U.S., U1124-00 is addressed in Chrysler service communication S2208000041. The documented next step is to use wiTECH and check Electric Coolant Heater (ECH) status in HCP > DATA. An ECH status of OFF is documented as normal operation; continue published service procedures.

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 U1124-00 mean?

For certain 2021–2022 Chrysler Pacifica vehicles in the U.S., U1124-00 is addressed in Chrysler service communication S2208000041. The documented next step is to use wiTECH and check Electric Coolant Heater (ECH) status in HCP > DATA. An ECH status of OFF is documented as normal operation; continue published service procedures.

2. Technical explanation

The verified manufacturer communication directs technicians to assess low-voltage and high-voltage system DTCs, U1008-00, U1124-00, and other related DTCs before replacing the heater. It states that cooling-system conditions (blockage, low coolant, or trapped air), heater low-voltage supply, and heater high-voltage supply must be assessed and resolved before heater replacement. For intermittent concerns, it directs cleaning and securing involved system-component grounds.

3. What system is affected?

High-voltage coolant heater / Electric Coolant Heater (ECH), with status viewed through the Hybrid Control Processor (HCP) DATA folder in wiTECH.

4. How serious is this code?

Not yet established by verified evidence.

5. Symptoms you may notice

Not yet established by verified evidence.

6. Possible causes

  • Cooling-system blockage.
  • Low coolant.
  • Trapped air in the cooling system.
  • Heater low-voltage supply issue.
  • Heater high-voltage supply issue.
  • For intermittent concerns, involved system-component ground condition.

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

  • Arrange diagnosis using wiTECH by a qualified service facility.
  • Have the ECH status checked in HCP > DATA.
  • Do not replace the heater solely on the presence of this DTC; the manufacturer communication requires assessment of cooling-system, low-voltage, and high-voltage supply conditions first.

10. Step-by-step troubleshooting

  1. Use wiTECH to verify high-voltage coolant-heater status.
  2. Locate Electric Coolant Heater status under HCP > DATA.
  3. If ECH status is OFF, the communication states ECH operation is normal; continue published service procedures.
  4. Perform service diagnostics for low-voltage and high-voltage system DTCs, U1008-00, U1124-00, and other related DTCs.
  5. Assess and resolve cooling-system blockage, low coolant, trapped air, heater low-voltage supply, and heater high-voltage supply issues before heater replacement.
  6. For intermittent concerns, clean and secure involved system-component grounds.

11. When to contact service

Service evaluation is appropriate because the verified procedure calls for wiTECH status verification and diagnostics of low-voltage, high-voltage, cooling-system, and ground conditions. Service urgency is not yet established by verified evidence.

12. What the service center may check

  • Read ECH status in wiTECH at HCP > DATA.
  • Diagnose low-voltage system DTCs.
  • Diagnose high-voltage system DTCs.
  • Diagnose U1008-00, U1124-00, and other related DTCs.
  • Assess cooling-system blockage, coolant level, and trapped air.
  • Assess heater low-voltage and high-voltage supply.
  • For intermittent concerns, inspect, clean, and secure involved system-component grounds.

13. Possible repair or resolution

  • Resolve identified cooling-system, heater low-voltage supply, heater high-voltage supply, and applicable DTC-related issues before considering heater replacement.
  • If the ECH status is OFF, ECH operation is documented as normal; continue with published service procedures.
  • Heater replacement is not established as the required repair by the supplied evidence.

14. Affected vehicles

15. Related TSBs / service bulletins

  • Chrysler service communication S2208000041, published through NHTSA on March 25, 2022. NHTSA manufacturer communication PDFs: MC-10220736-9999, MC-10212339-9999 (RevA), MC-10223118-9999, and MC-10229080-9999. Source: https://static.nhtsa.gov/odi/tsbs/2022/MC-10220736-9999.pdf

16. Recall information

  • Not yet established by verified evidence.

17. Official manufacturer information

Verified applicability: Chrysler Pacifica, model years 2021–2022, U.S. The supplied official NHTSA-hosted manufacturer communication identifies wiTECH HCP > DATA as the location for ECH status and states that OFF indicates normal ECH operation.

19. Frequently asked questions

What does an ECH status of OFF mean?

The verified Chrysler service communication states that ECH operation is normal when the status is OFF.

Where is the ECH status found?

The communication states that Electric Coolant Heater status is found in wiTECH under HCP > DATA.

Should the electric coolant heater be replaced immediately?

No immediate heater replacement is established by the supplied evidence. The communication requires assessment and resolution of cooling-system, heater low-voltage supply, and heater high-voltage supply issues before heater replacement.

Which vehicles are verified as applicable?

The supplied applicability record identifies U.S.-market 2021–2022 Chrysler Pacifica vehicles.

20. Sources & verification

Verified
Chrysler U1124-00: Use wiTech to verify the HV coolant heater status.… | EV Diagnostics