Sealey FF400 Open and Short DC Circuit Tester

Introduction

Thank you for purchasing a Sealey product. Manufactured to a high standard, this product will, if used according to these instructions and properly maintained, give you years of trouble-free performance.

IMPORTANT: Please read these instructions carefully. Note the safe operational requirements, warnings & cautions. Use the product correctly and with care for the purpose for which it is intended. Failure to do so may cause damage and/or personal injury and will invalidate the warranty. Keep these instructions safe for future use.

Safety

General Safety Instructions

• [Recommended] Familiarise yourself with the application and limitations of the tester as well as the potential hazards. If in any doubt consult a qualified electrician.
• [Prohibited] Do not apply voltage or current to the meter that exceeds the specified maximum.
• [Recommended] Only for use with DC voltages.
• [Prohibited] Do not connect to a circuit exceeding 42V DC under any circumstances.
• [Prohibited] Do not use on AC voltages.
• [Prohibited] Do not use on any circuit directly or indirectly connected to AC lines or any other AC power source.
• [Prohibited] Do not use with any component or circuits of the ignition system.
• [Recommended] Modern vehicles contain extensive electronic systems. You are required to check with the vehicle manufacturer for any specific instructions regarding the use of this type of equipment on each vehicle.
• No liability will be accepted for damage/injury where this product is not used in accordance with all instructions.
• [Recommended] When not in use, store the meter carefully in a safe, dry, childproof location. Storage temperature range: -10°C to 50°C.

Personal Precautions

• When using this tester, please observe all normal safety rules concerning:
• Protection against the dangers of electronic current.
• Protection of the meter against misuse.
• [Prohibited] Do not use leads if damaged or if the wire is bared in any way.

Product Overview

Find short and open circuits fast and easily. Simply attach the sender unit to the circuit and follow the wires using the detector. Ideal for automotive repairs. Suitable for all DC circuits up to 42V. Supplied in a carry-case. Powered by two 9V batteries.

The tester consists of a sender unit and a receiver unit with a probe. The sender has a rotary switch and a selection switch. The receiver has a probe tip.

Operation

How to Use the Probe

The probe of the receiver is built of coiled steel and may be bent as needed to reach wires in congested areas. Depending on the circuit characteristics and sensitivity settings, the probe will pick up the signal from the wire in a range of positions. For the best possible range, the receiver's probe tip (black cap) should be positioned perpendicular (at 90°) to the wire being traced, either above or below it.

Diagram Description (fig.1): Diagram showing the correct and incorrect positioning of the receiver probe relative to a wire for optimal signal detection. The correct position shows the probe perpendicular to the wire. The incorrect position shows the probe parallel to the wire, leading to a weak or no signal.

Locating Short Circuits

1. Connect the sender in series with the short-circuited wire, ensuring one of the test leads is connected to the circuit's positive supply (or to the negative for vehicles with positive supply connected to the chassis). A fuse socket (in place of a blown fuse) or connector provides a convenient connection point.
2. Set the sender's switch to "Tone". The red LED should light. If the red LED is dim or does not light, check the battery. Set the receiver's rotary switch to a medium sensitivity position.
3. Move the probe along the wire; the receiver should emit a tone.
4. Follow the wire or check at different points, starting from the sender and moving towards the load. An audio signal (beeping sound) indicates the integrity of the circuit. If the beeping stops, it indicates that the probe has passed beyond the short circuit point.
5. If it is difficult or impossible to get the receiver to pick up any signal, adjust the rotary switch of the receiver and check again.
6. The short circuit is located in the area where the audio signal stops or changes significantly.

Wire Tracing

Wire tracing hook-up and procedures are essentially the same as for locating short circuits. The sender treats the load (light, accessory, etc.) as the short circuit or connection to ground. For wire tracing, simply follow the wire with positive (beeping) audio indicator feedback from the tracer, from the source to the load.

For step-by-step instructions, please refer to section 3.2 "Locating Short Circuit".

Locating Open Circuits

WARNING! Observe the limits and safety precautions at all times.

1. Connect the sender in series with the open-ended wire, ensuring one of the unit's clips is connected to the circuit's positive supply or ground. A fuse socket (with fuse removed) or connector provides a convenient place as shown in the diagrams.
2. Ensure the clips are firmly attached to their connection points and set the sender's switch to "Tone". If connected elsewhere than a fuse socket, check that the circuit fuse is installed and in working condition (not open). If necessary, replace with a new fuse of the same rating.
3. Switch the receiver on and adjust the rotary switch for the correct sensitivity.
4. Slowly sweep the wire with the receiver, ensuring the probe is perpendicular and above or below the wire being traced, and as close to it as possible.
5. Follow the wire or check at different points, starting from the sender and moving towards the load (accessory, light, etc.), observing the probe positioning as indicated above. Continue this procedure while the audio signal (beeping sound) indicates circuit integrity. If the beeping stops, it indicates that the probe has passed beyond the open, break, or bad connection in the circuit.
6. Double-check by positioning the probe before and after the suspected location. If the open circuit point has been found, the audio indicator will show circuit integrity on one side and not the other.
7. At this point, where the audio signal stops, you have found the open circuit.

Wire Identification

NOTE! For connection, refer to hook-up options. Wiring can be identified by following the hook-up procedures for short and open circuits, depending on the particular configuration of the circuit.

• For identifying wires with a load connected: Connect the sender as described in section "Locating Short Circuit" to the circuit to be identified. Then, scan all suspected wiring with the receiver's probe until the beeping is at its maximum. In tightly packed wires (bundles, conduits, etc.), it may be necessary to spread them apart to facilitate the identification process of a particular wire.
• For identifying wires without a load connected: Connect the sender as described in section "Locating Open Circuit" to the circuit to be identified. Then, scan all suspected wiring with the receiver's probe until the beeping is at its maximum. In tightly packed wires (bundles, conduits, etc.), it may be necessary to spread them apart to facilitate the identification process of a particular wire.

Special Tracing Procedures

In all cases, first set the receiver at the lower sensitivity level and increase it as necessary. Proceed as indicated in the sections of this user's manual applicable to your situation. After locating a probable fault area, always verify several points in the wires on both sides of the suspected fault. This procedure helps avoid confusing signal loss with the actual trouble point.

Wire Bundles and Conduits

Special care should be taken when tracing a wire inside a bundle or conduit that has a split. In this case, it may be possible to follow the wrong branch for a short distance and still receive a positive audio indication. The probe may be picking up the signal from another nearby branch (the one actually being traced). To avoid following the wrong path, the branches should be swept while maintaining the probe outside the apex area between the split, as shown in fig.2. Careful attention should be paid to the beeping of the tracer unit indicator, as it provides the necessary feedback to evaluate the proximity of the wire being traced.

Diagram Description (fig.2): Diagram illustrating how to trace a wire within a bundle or conduit that has a split. It shows that the probe should be positioned outside the apex area of the split to avoid picking up signals from adjacent wires, which could lead to incorrect tracing.

To Increase Pickup Range When Tracing Wires

• When tracing or identifying wires connected to a lightly loaded circuit (low currents), the pickup range is reduced significantly. A possible solution is, after connecting the sender in series with the circuit to trace, to replace the load (light bulb, module, etc.) with a direct connection to ground. This allows the sender to inject a more powerful signal that is easier to detect.
• For cases in which it is suspected that the layout of the wires is the cause of a difficult pickup or weak signal, a dramatic increase of the range can be accomplished by spreading the circuit. This is achieved by connecting a jumper wire between the sender's live wire and a ground point (fig.3) somewhere else on the vehicle. This last method should be used only as a last resort and with the receiver set to low sensitivity, as it may make pinpointing the precise location more difficult due to the much increased range.

Diagram Description (fig.3): Diagram showing how to increase the pickup range for tracing wires. It illustrates connecting the sender to the circuit and then using a jumper wire to connect the sender's live wire to a ground point elsewhere on the vehicle, especially useful for low-current circuits or complex wiring layouts.

[Recommended] Always verify that the sender is connected in series with the circuit being tested, as this confirms a proper connection and will limit the amount of current flowing in the circuit.

Circuits with Multiple Loads or Branches

When tracing circuits connected to, or powering, multiple loads and/or branches, and when these circuits are active or live, the bulk of the current injected into the circuit by the sender will be directed to the short-circuited branch. However, smaller amounts of current (or stray current) will flow elsewhere, making the tracing procedure confusing or even misleading.

The simplest and most effective way to deal with these cases is to disconnect or remove all loads from the circuit being traced (e.g., remove the light bulbs in fig.4).

Diagram Description (fig.4): Diagram illustrating a circuit with multiple loads (light bulbs) connected via a fuse socket and battery. It shows the path of 'short circuit current' flowing through a shorted bulb and 'stray current' potentially flowing through other components, which can complicate tracing.

Maintenance

WARNING! Do not attempt to repair or service your FF400 unless you are qualified to do so. To avoid damage to the FF400, do not get water inside the case.

• Periodically wipe the case with a damp cloth and mild detergent. Do not use solvents.
• Turn the sender and receiver off when not in use and remove the batteries if stored for a long period of time.
• Do not store in a place of high humidity or high temperature.

Battery Replacement

To replace the batteries on either the sender or the receiver, simply undo the Phillips screw on the rear of the unit's battery cover and replace the battery with a 9V PP3.

Environmental Protection

Recycle unwanted materials instead of disposing of them as waste. All tools, accessories, and packaging should be sorted, taken to a recycling centre, and disposed of in a manner compatible with the environment.

When the product becomes completely unserviceable and requires disposal, drain off any fluids (if applicable) into approved containers and dispose of the product and fluids according to local regulations.

WEEE Regulations

Dispose of this product at the end of its working life in compliance with the EU Directive on Waste Electrical and Electronic Equipment (WEEE). When the product is no longer required, it must be disposed of in an environmentally protective way. Contact your local solid waste authority for recycling information.

Battery Removal

Under the Waste Batteries and Accumulators Regulations 2009, Jack Sealey Ltd is required to inform potential purchasers of products containing batteries (as defined within these regulations) that they are registered with Valpak's registered compliance scheme. Jack Sealey Ltd's Batteries Producer Registration Number (BPRN) is BPRN00705.

Notes and Warranty

NOTE: It is our policy to continually improve products and as such we reserve the right to alter data, specifications, and component parts without prior notice.

IMPORTANT: No liability is accepted for incorrect use of this product.

WARRANTY: Guarantee is 12 months from purchase date, proof of which will be required for any claim.