Sokkia E001 Error: What It Means and How to Fix It

Applies to: CX-50, CX-60, CX-101, SET630R

What Does E001 Mean?

E001 on Sokkia total stations (CX series, SET series) indicates a fault in the ATR (Automatic Target Recognition) system — the camera-based system that automatically finds and tracks prism targets. Sokkia's ATR uses a CCD sensor to detect the prism's infrared retroreflection and center the line of sight automatically. E001 appears when the ATR system fails to acquire a target, loses track, or detects an internal sensor fault.

E001 can be an environmental condition (target out of range or obscured) or a hardware fault (ATR sensor failure). Environmental causes are far more common and are field-resolvable; hardware ATR faults require service.

Common Causes of E001

• Prism out of the ATR search window — the target is not in the field of view when ATR searches
• Target obscured by dust, rain, or vegetation between the instrument and prism
• Prism face not oriented toward the instrument — single-face prisms must face the total station
• Excessive ambient light (direct sun on the prism face) overwhelming the ATR's infrared detection
• ATR CCD sensor contaminated or damaged
• ATR optical system misaligned from impact

How to Fix Sokkia E001 — Step by Step

1. Manually aim the instrument at the prism using the eyepiece, then activate ATR search.
2. Ensure the prism face is oriented directly toward the instrument.
3. Check for obstructions between instrument and prism — clear any dust, rain, or vegetation.
4. If in direct sun, shade the prism or wait for cloud cover — solar saturation of the prism face prevents ATR detection.
5. Try a fresh ATR calibration: set up on a known prism location, activate ATR calibration per the CX-series manual.
6. If ATR fails consistently with clear line of sight to a properly-oriented prism, the ATR sensor needs service.

When to Send It In for Service

ATR sensor replacement and calibration at Sokkia service center. Turnaround 10-14 business days. Cost $400-700 for CCD replacement and full instrument calibration.

Preventing E001 in the Future

Protect the ATR optical window from impacts. Keep the instrument covered when not in use to prevent dust accumulation on the ATR optics. Calibrate ATR at the start of major projects.

Related Error Codes

Sokkia Total Station Error E003 | Sokkia Total Station Error E005 | Sokkia Total Station Error E004