Audi P18F100
Function limitation due to deviating wheel speeds (passive/intermittent). The noise can no longer be heard in the following circumstances: • If the vehicle is rolling in position "
Quick answer
P18F100 is documented by Audi as “Function limitation due to deviating wheel speeds.” For certain U.S. 2022–2023 Audi Q4 e-tron vehicles, Audi publications describe two distinct service contexts for this code: an intermittent electrical-system warning associated with possible damaged pins, and a reproducible noise concern with P18F100 stored passively/intermittently in electric drive control unit J841.
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 P18F100 mean?
P18F100 is documented by Audi as “Function limitation due to deviating wheel speeds.” For certain U.S. 2022–2023 Audi Q4 e-tron vehicles, Audi publications describe two distinct service contexts for this code: an intermittent electrical-system warning associated with possible damaged pins, and a reproducible noise concern with P18F100 stored passively/intermittently in electric drive control unit J841.
2. Technical explanation
Verified Audi/NHTSA manufacturer communications identify P18F100 as a wheel-speed-deviation function limitation. One Audi communication states that P18F100 may be logged as passive/intermittent in electric drive control unit J841 (address 0051) when a customer-reported condition can be reproduced. A separate Audi bulletin lists P18F100 among codes that may be stored in Electric Drive 2, J944 (address 00CE), with an intermittent instrument-cluster message: “Electrical system: fault. Please contact workshop.” That bulletin says pins may have been damaged during an end-of-line production check. The supplied evidence does not establish that every occurrence of P18F100 has the same cause.
3. What system is affected?
Electric drive system. Verified documents reference electric drive control unit J841 (address 0051) and Electric Drive 2, J944 (address 00CE).
4. How serious is this code?
Not yet established by verified evidence.
5. Symptoms you may notice
- An intermittent instrument-cluster message: “Electrical system: fault. Please contact workshop.” is documented in one Audi bulletin context.
- A customer-reported noise is documented in a separate Audi bulletin context.
- P18F100 may be stored as passive/intermittent in electric drive control unit J841 (address 0051).
6. Possible causes
- For the Audi bulletin concerning the intermittent electrical-system warning and codes in Electric Drive 2/J944, pins may have been damaged during an end-of-line production check.
- For other P18F100 occurrences, a cause is 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 “Electrical system: fault. Please contact workshop.” appears, arrange diagnosis by an Audi service provider.
- Record the warning message, whether it is intermittent, any noise concern, and the stored diagnostic codes for the service visit.
- Do not disconnect wheel-speed-sensor connectors or perform high-voltage/electric-drive repairs yourself.
10. Step-by-step troubleshooting
- Have a qualified Audi technician retrieve fault memory and identify whether P18F100 is stored in J841 (address 0051) or Electric Drive 2/J944 (address 00CE).
- For the intermittent electrical-system-warning bulletin context, have the technician follow the applicable Audi service bulletin procedure for the referenced wiring/pin concern.
- The supplied evidence notes that, in the noise-related bulletin context, the noise is no longer heard when the vehicle is rolling in N or when a wheel-speed-sensor wiring-harness connector on the affected axle is disconnected. This is workshop diagnostic information, not a user repair procedure.
11. When to contact service
Contact an authorized Audi service provider for diagnostic evaluation, particularly if the electrical-system warning message is displayed or a noise concern is present.
12. What the service center may check
- Retrieve and document all stored DTCs in J841 (address 0051) and Electric Drive 2/J944 (address 00CE), as applicable.
- Assess whether the reported condition matches the applicable Audi bulletin context: intermittent electrical-system warning or reproducible noise.
- For the J944 bulletin context, inspect and address the documented possible damaged-pin condition using Audi service procedures.
13. Possible repair or resolution
- Audi states that wiring-harness assembly was optimized during production for the damaged-pin bulletin context.
- The specific field repair resolution is not fully established by the supplied verified evidence.
14. Affected vehicles
- Audi Q4 e-tron · 2022 · US
- Audi Q4 e-tron · 2022–2023 · US
15. Related TSBs / service bulletins
- Audi/NHTSA Manufacturer Communication 10230846, published January 17, 2023: addresses intermittent “Electrical system: fault. Please contact workshop” warnings and lists P18F100, U140500, and P0A1B00 in Electric Drive 2/J944; notes possible damaged pins during end-of-line checking. https://static.nhtsa.gov/odi/tsbs/2023/MC-10230846-0001.pdf
- Audi/NHTSA Manufacturer Communication 10227033, published November 18, 2022: earlier communication covering the same intermittent warning/code context and possible damaged pins. https://static.nhtsa.gov/odi/tsbs/2022/MC-10227033-0001.pdf
- Audi/NHTSA Manufacturer Communication 10226249, published November 4, 2022: documents P18F100 as passive/intermittent in J841 (address 0051) in a noise-related service context. https://static.nhtsa.gov/odi/tsbs/2022/MC-10226249-0001.pdf
16. Recall information
- Not yet established by verified evidence.
17. Official manufacturer information
Verified source material consists of Audi manufacturer communications published through NHTSA. Applicability supplied with this diagnostic is U.S. Audi Q4 e-tron model years 2022–2023.
19. Frequently asked questions
What does P18F100 mean?
Audi documents P18F100 as “Function limitation due to deviating wheel speeds.”
Is P18F100 always caused by damaged pins?
No. Damaged pins are documented in one specific Audi bulletin context involving an intermittent electrical-system warning and Electric Drive 2/J944. The supplied evidence does not establish that this is the cause of every P18F100.
Can I safely drive or charge with P18F100?
Not yet established by verified evidence.
Which vehicles are covered by the supplied applicability data?
U.S. Audi Q4 e-tron vehicles from model years 2022 through 2023.