CYA Cables

ST-7 Instructions

7-Pin Socapex cable tester — how to use it, read the display, charge it, and take care of it.

Overview

The ST-7 tests 7-pin Socapex cables for opens, shorts, and wire swaps (including multi-wire cycles). Results appear in under one second. It can report up to four simultaneous faults.

The kit has two units. The cable under test connects between them:

• Female Testing Unit — display, battery, and power switch
• Male Testing Unit — mates to the other end of the cable (no power or charging required)

Safety

What’s in the box

Item	Description
Female Testing Unit	Display, battery, power switch, and USB-C charging port
Male Testing Unit	Second half of the kit — no battery or charging required
USB-C Cable	For charging the Female Testing Unit
Instruction Card	Laser-etched aluminum card with basics and a QR code to this page
Hard Case	IP65 protective case for transport and storage. External dimensions: 9.25 × 7.5 × 4.25 in (235 × 191 × 108 mm). Full kit with case: 2.95 lb (1.34 kg). Always store the kit in the case when not in use.

Charging & power

Charging

Charge the Female Testing Unit before first use and whenever the battery is low. The Male Testing Unit does not need charging.

1. Connect the provided USB-C cable to the port on the Female Testing Unit.
2. Connect the other end to a USB power source (5 V, 1 A minimum).
3. Red LED = charging.
4. Green LED = fully charged.
5. Disconnect the cable when charging is complete.

With the screen on and no changing results, runtime is about 30 hours on a full charge. During normal use, results appear in under one second; keep the switch held a few more seconds to read the display. At roughly 5–10 seconds of on-time per cable, a full charge supports on the order of 10,000–20,000+ tests — typically many shop days or full show weeks between charges. A fully discharged battery usually takes about 1–2 hours to recharge.

Power on / off

The Female Testing Unit uses a momentary power switch:

• On: Press and hold. The display initializes (a brief flash of pixels is normal), then shows the result in under one second.
• Off: Release the switch. The unit powers off immediately.

Press and hold while checking a cable and reading the result, then release. That conserves battery life.

Testing a cable

1. Verify the cable is disconnected from all power sources (see Safety).
2. Connect the cable between the Female Testing Unit and the Male Testing Unit:
   • One end into the Female Testing Unit
   • The other end into the Male Testing Unit
3. Press and hold the power switch on the Female Testing Unit.
4. Read the display — the result appears in under one second; hold as long as you need to read it.
5. Release the power switch to turn off.

Self-check

To confirm the tester itself is working, mate the Female Testing Unit and Male Testing Unit directly together (no cable between them) and press and hold the power switch. The display should show a perfect result — all seven pins green.

Reading the display

The round color display shows seven pin positions. Pins 1, 2, 3, 4, 6, and 7 sit around the ring, each labeled with its number. The center position is pin 5 — it shows the CYA logo instead of a digit. Color and style show pin status the same way for every pin, including pin 5.

Pin status

Full-screen states

What you see	Meaning
All 7 pins green	Perfect — cable wired correctly, no faults
One or more pins red / yellow	Fault — fault(s) shown on the pins involved
Red stop sign (5+ faults)	Do not use — five or more simultaneous faults; inspect or replace the cable
“NO CABLE DETECTED!”	Disconnected — no cable connected, or cable completely severed

Intermittent faults

If a short (or other fault) is detected and then clears while you keep holding the switch (for example while flexing or reseating a connection), the ST-7 keeps a red outline and red link on the pins that had the fault, even after those pins go back to green. That leaves a trace of the intermittent problem so it is harder to miss.

Display examples

These screens match what you see on the ST-7’s round display.

Perfect cable

All seven pins green. The cable is wired correctly with no opens, shorts, or swaps. The same display appears on a successful self-check (units mated with no cable).

Open circuit

Pin 3 shows a black center with a red ring — that conductor is open. Other pins remain green.

Short between two pins

Pins 1 and 2 are filled red and joined by a red bar — those conductors are shorted together.

Multi-pin short

Pins 2, 5 (center), and 3 are all shorted to pin 1 — red fills and red links between them. Pins 4, 6, and 7 remain good.

Swapped conductors

Pins 1 and 2 are red with a yellow double-arrow — those two wires are transposed.

Mixed faults

Multiple issues at once: pins 1 and 2 swapped (yellow arrows), pin 3 open (black with red ring), and pin 6 shorted to pin 5 (center) — red fill and red link. Pins 4 and 7 remain good.

Intermittent short

Pins 1 and 2 are green again (currently testing good), but a red outline and red bar remain — the tester previously detected a short between those pins that has since cleared.

No cable detected

All pins black with red rings and “NO CABLE DETECTED!” — nothing is connected between the units, or the cable is completely open end-to-end.

Known limitations

1. Pins 1 and 3 both open

If pins 1 and 3 are both open at the same time, pin 1 may not appear as a separate open on the display. If you need to confirm pin 1 in that situation, inspect the cable or verify that conductor another way.

2. Five or more faults

The ST-7 reports up to four simultaneous faults. Five or more shows a red stop sign — do not use the cable; inspect or replace it.

3. Complex multi-fault cables

On cables with several faults at once, more than one wiring problem can look the same on the tester. Treat the display as the best single reading; for heavily damaged cables, open it up or replace it when in doubt.

Care & storage

• Charge only with the provided USB-C cable and a 5 V USB source (1 A or higher).
• Do not operate the ST-7 while it is charging.
• For long storage, charge to about 50% before putting the kit away.
• Always store both units in the IP65 hard case with the cable and instruction card.
• Do not expose the units to water or moisture. Avoid extreme heat (hot vehicles, direct sun) and freezing storage when possible — protect the LiPo battery.
• Inspect connector pins for debris, bends, or corrosion. Do not force mates. Clean with a dry lint-free cloth or compressed air.
• Clean the display window with a dry, soft cloth only — no solvents or abrasives.

Troubleshooting

Problem	Likely cause	What to try
Display stays blank when powered on	Battery dead	Charge via USB-C for at least 30 minutes, then retry
“NO CABLE DETECTED!”	No cable, or cable fully severed	Connect a cable between both units; if already connected, inspect for a complete cut. Run a self-check (units mated, no cable) to confirm the kit itself is OK
Stop sign on a cable you believe is good	Real multi-fault, or poor mate	Reseat both ends; compare with a known-good cable; run a self-check
Self-check is not all green	Units not fully mated, or unit fault	Reseat Female and Male Testing Units directly together; charge the Female Testing Unit; if still wrong, contact CYA Cables
Won’t power on after charging	Battery or switch issue	Confirm charge LED behavior; if still dead, contact CYA Cables
Red charge LED never lights	Already full, or bad USB source	Try another USB supply; green LED means already full

Specifications

Spec	Value
Cable type	7-pin Socapex
Fault detection	Up to 4 simultaneous faults (opens, shorts, swaps/cycles)
Detection time	Under 1 second
Display	240×240 round color display
Battery	1000 mAh rechargeable LiPo (Female Testing Unit)
Charging	USB-C, 5 V / 1 A minimum
Charge indicators	Red = charging, green = full
Runtime (screen on, static)	Approx. 30 hours
Tests per charge (est.)	On the order of 10,000–20,000+ at ~5–10 s hold per cable
Power switch	Momentary (hold on, release off)
Kit weight (with case)	2.95 lb (1.34 kg)
Case	IP65; external 9.25 × 7.5 × 4.25 in (235 × 191 × 108 mm)
Male Testing Unit	No power or charging required