Trailer antilock brakes (ABS)
Section 6.3 of the Kentucky CDL Manual (p. 6-6) covers trailer antilock brakes and their warning lamp. It is tested on the Combination Vehicles test.
Key facts
| Part of | the Combination Vehicles test (80% to pass) | KY CDL Manual, front section pp. 2-3 |
|---|---|---|
| Manual section | §6.3 Trailer antilock brakes | KY CDL Manual p. 6-7 |
| Questions in CDL Mile's bank | 4 | CDL Mile, checked against KY CDL Manual |
Key rules
- § 6.3.2p. 6-7
ABS is an extra on top of the normal brakes, so if it fails your regular brakes still work. Keep driving normally, but have the ABS serviced soon.
Braking with ABS
Try two questions
Combination Vehicles · Trailer antilock brakes
In normal driving, how does the manual tell you to brake a tractor-trailer that has ABS?
Tap an answer to see the explanation and the manual page.
Combination Vehicles · Trailer antilock brakes
How does ABS change your braking, according to the manual?
Tap an answer to see the explanation and the manual page.
More Combination Vehicles topics
Sources
Kentucky Commercial Driver's License Manual, version March 2025, Kentucky State Police. Page references are to its printed page numbers. CDL Mile is independent and not affiliated with Kentucky State Police.
Updated for the March 2025 Kentucky CDL manual. Last checked November 5, 2026.
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