“Check Headlamp System See Manual” indicates a fault in the headlamp system. Start by checking which side and lighting functions are affected, then have the cause diagnosed. The warning alone does not confirm that an LED module needs replacing.
Depending on the findings, resolving the warning may involve repairing a connection, replacing a defective LED module or headlamp assembly, or completing configuration after replacement.
What should you check first?
Park somewhere safe and check the front lights. Note whether the problem affects the left side, right side or both. Check the dipped beam, main beam, daytime running lights and indicators.
If lighting needed for visibility is not working reliably, avoid driving in darkness or poor visibility and arrange assistance. A recurring warning needs investigation even when the lights appear to operate normally.
| What you notice | What to check next |
| One headlamp or lighting function fails | Identify the affected side and function to help direct diagnosis. |
| Both headlamps are affected | Note any additional warnings so shared electrical supplies and controls can be considered. |
| Lights flicker or work intermittently | Note when the fault occurs, including weather conditions and recent repairs. |
| A lamp is damaged or contains pooled water | Have the housing and electrical components inspected. |
| The warning appeared after replacement | Recheck compatibility, connections and any required coding. |
These symptoms help narrow the investigation. They do not identify the failed component by themselves.
What can cause the headlamp warning?
Possible causes to investigate include a defective LED module, damaged wiring or connectors, a fault within the headlamp assembly, or an outstanding configuration requirement after replacement.
The LED module and complete headlamp assembly are different components. A module replacement will not repair a cracked lens or damaged housing. Equally, replacing the complete headlamp may be unnecessary if testing identifies a separately replaceable module as the cause.
This is why diagnosis should come before ordering parts.
How is the fault diagnosed?
Check for an applicable recall
Before purchasing a replacement, check the vehicle identification number through Ford’s UK recall service, or ask a Ford dealer to check it.
Recall eligibility depends on the individual vehicle and market. A headlamp recall affecting another Mach-E does not establish that your vehicle has the same fault or requires the same repair.
Inspect the headlamp and connections
The inspection should consider the lamp housing, wiring, connectors and evidence of water ingress. Recent accident damage, headlamp replacement or electrical work can help direct the investigation.
Light mist inside the lens is not automatically evidence of a defective lamp. Ford’s Mach-E guidance distinguishes normal condensation from pooled water, streaks or large droplets that require inspection. Refer to the manual applicable to your vehicle. Ford Mach-E headlamp condensation guidance
If water ingress is confirmed, its source needs attention as part of the repair.
Have the lighting system scanned and tested
Diagnostic equipment must be capable of accessing the relevant vehicle systems. Fault codes guide testing, but a code alone may not establish which component needs replacement.
A communication-related fault, for example, does not automatically mean the hardware is working correctly. Connections, electrical supplies and the component itself may still need checking.
Before agreeing to replacement, establish what testing supports the diagnosis and whether coding will be required afterwards.
When should the LED module be replaced?
LED module replacement is appropriate when testing identifies it as defective and the replacement matches the vehicle’s headlamp application.
Confirm the original module markings and headlamp specification before ordering. Similar-looking modules can have different applications, and a different part-number suffix should not be assumed interchangeable.
If the lamp housing is damaged or water ingress is present, address those findings alongside the electrical fault.
Checking the LC5A-13B626-AG LED module
When diagnosis identifies the relevant LED module as faulty, compare its markings with the replacement specifications.
The FoMoCo LC5A-13B626-AG LED module has the following identification references:
| Identifier | Part numbers |
| FoMoCo LED module number | LC5A-13B626-AG |
| Continental manufacturer number | A2C7636130500 |
| Ford references | 5737129, LC5Z-13C788-E and LJ8Z13C788E |
Check the original LED module number, headlamp assembly reference, vehicle details and lighting specification. Confirm the application before ordering rather than relying on the model name or year alone.
Does the replacement LED module need programming?
The LC5A-13B626-AG LED module specifications state that coding is required after replacement. Arrange this before installation so the replacement process can be completed correctly.
The procedure must suit the vehicle and component. Do not assume that a generic reset or configuration procedure applies to every Mach-E lighting controller.
After installation and any required coding, check the affected lighting functions and reassess relevant diagnostic faults. Clearing the dashboard message is only one part of verifying the repair.
Why might the warning remain after replacement?
A continued warning does not automatically mean the replacement LED module is defective.
| Check | Why it matters |
| Component identification | The replacement must match the headlamp application. |
| Connectors and wiring | An unresolved connection fault can remain after replacement. |
| Required coding | Physical installation may need to be followed by configuration. |
| Damage or water ingress | The original source of damage may still be present. |
| Remaining diagnostic faults | Another component or circuit may require attention. |
Compare the findings before and after repair. Replacing further parts without identifying the remaining fault can increase the cost without resolving the warning.
What to confirm before repair
Before proceeding, establish:
- Which side and lighting functions are affected.
- Whether the fault is constant or intermittent.
- Which component testing has identified as defective.
- The correct replacement reference and headlamp application.
- Any coding required after replacement.
The repair should restore correct lighting operation and resolve the diagnosed fault, rather than simply remove the warning from the display.
Parts and Compatibility List
To ensure you order the correct replacement part for your vehicle, cross-reference your vehicle details and existing headlight tags with the part numbers below.
Continental part numbers
- A2C7636130500
FoMoCo part numbers
- LC5A-13B626-AG
- LC5A13B626AG
Ford part number
- 5737129
- LC5Z-13C788-E
- LC5Z13C788E
- LJ8Z13C788E
More compatible part numbers
- LC5A-13B626-AK
- A2C7764670100
- NC5A-13B626-FB
- A2C7830820700
Compatible Ford Mustang Mach-E Basic Base ECE Reflector LED headlamps
- LJ8B13035BG
- LJ8B13E014BF
- LJ8B13E015BF
- LJ8B13E014BE
- LJ8B13E014CE
- LJ8B13E014BE
- LJ8B13E014CF
- LJ8B13E015CF
Compatible Ford Mustang Mach-E Basic Base FNA Reflector LED headlamps
- LJ8B13E014AD LJ8B-13E014-AD
- LJ8B13E015AF
Compatible Ford Fiesta MK8 VIII Adaptive Ford LED headlamps
- N1BB-13E015-BF
- N1BB-13E016-BF
- N1BB-13E016-BG
- N1BB-13E017-BG
Compatible Ford Expedition XLT LED headlamps
- NL1B-13E014-BH
- NL1B-13E015-BH
- NL1B-13E014-BP
- NL1B-13E015-BP
Compatible cars
- Ford Fiesta MK8 VIII ST3
- 1.0 EcoBoost 12V Hybrid Petrol
- 2019 2020 2021 2022 2023
- Ford Mustang Mach-E EV
- 2021 2022 2023 2024
- Ford Expedition XLT
- 2022