Tech Tips: Identifying Intermittent ABS Faults
Intermittent ABS issues are one of the most frustrating problems for trailer techs. One day, everything checks out. The next day, the trailer rolls into a DOT checkpoint and lights up the violation list. Why?
Because these aren’t obvious, constant faults — they’re signal drops, sensor inconsistencies, or power issues that don’t fail until the trailer is moving or bouncing down the road.
Here’s how to track down intermittent ABS faults before they cost you time, money, and CSA points.
Understand the Nature of Intermittent ABS Faults
Unlike hard faults, intermittent issues don’t always trigger warning lights — especially during a quick yard walkaround. Some faults may clear themselves temporarily, only to return during specific conditions:
Vibration during travel
Moisture or temperature changes
Loose sensor wiring or corroded connectors
Weak power supply from the truck
These faults often go unnoticed until enforcement gets involved — which makes them a serious risk.
Use the Inspector 930 to Catch the Quiet Failures
The Inspector 930 is one of the only tools that lets a tech pull stored and active ABS fault codes directly from the trailer — without a tractor attached.
That means you can:
Detect lingering faults before they go active
View power irregularities at the ABS ECU
Test ABS lamp functionality and signal control
Identify weak or fluctuating sensor signals
Because the Inspector 930 uses the same diagnostic protocols enforcement does, you’ll catch the same issues they would — just before they do.
Daily Checks: What to Include
If your fleet deals with ABS inconsistencies, here’s what to incorporate into your daily or pre-load inspection using the Inspector 930:
ABS Power Verification
Confirm ECU power-up
Check for any voltage drop
ABS Fault Code Pull
Capture both active and stored DTCs
Log and clear codes only after verification
ABS Lamp Test
Make sure the ABS warning light cycles properly
Confirm visibility from the tractor position
Physical Connector Check
Inspect ABS wiring at the axle and control box
Clean and secure the 7-way and power leads
This daily habit helps narrow down repeat issues and builds a pattern of preventative action — not reactive scrambling.
Tip: Track Repeat Offenders
Some trailers become chronic ABS headaches. Use a basic tracking system — or a digital tool like Sentry — to flag trailers with repeat ABS trouble.
This helps you:
Prioritize inspections on known problem units
Catch degrading systems early
Build a history that’s DOT-audit ready
Repeat failures usually point to wiring fatigue, worn sensors, or ECU corrosion — all of which the Inspector 930 can help detect during each test cycle.
Fix What You Can’t See — Before It Becomes a Violation
If you’re relying on visual inspections or only catching faults when the ABS lamp activates, you’re running behind the problem. The Inspector 930 puts your team ahead of the issue — giving them full visibility into electrical faults, ECU behavior, and sensor integrity.
No more guessing. No more “it looked fine yesterday.” Just tested, verified results.
To see how the Inspector 930 helps eliminate intermittent ABS headaches, visit:
📍 lite-check.com/shop/inspector-930
or call 509-535-7512 to talk with a Lite-Check diagnostics expert.