Explaining Technical Failures with New Equipment

Read/Listen first

Yesterday we ran a long test on the simulator with the new battery pack, and something went wrong. The prototype had worked perfectly for months, but during this test the series battery suddenly failed after only two hours. We discovered that the temperature inside the battery module was rising much faster than in our earlier tests. Because of this battery failure, the whole simulator shut down in the middle of a training scenario, and we had to cancel the session. Since then we have repeated the test several times, and we have seen the same problem again. If we don’t find the root cause this week, we will have to delay the retrofit schedule for the client. We need to explain clearly to them that the supplier is working with us, that the test campaign is still running, and that the final system will be safe and reliable.

⚡ Learning goals

• Can explain a technical failure clearly to a non-technical client.
• Can describe past tests and current actions using past and present perfect forms.
• Can outline possible consequences and next steps using conditional sentences.

✨ Key language

• We discovered that… “We discovered that the new battery overheated during the long test.”
• Because of this failure,… “Because of this failure, the simulator shut down mid-session.”
• If we don’t…, we will have to… “If we don’t fix this, we will have to delay delivery.”

⚙️ Rules & Grammar — 4 Structures

1️⃣ Past simple for completed tests

Rule: Use the past simple to describe finished actions at a specific time in the past.
Examples: We ran a long test yesterday.; The battery failed after two hours.; The simulator shut down during training.
Common pitfall + fix: Learners often mix past simple with present perfect. — Use past simple when the time is finished (yesterday, last week).

2️⃣ Present perfect for recent repeated tests

Rule: Use the present perfect to talk about experiences or actions that started in the past and are still relevant now.
Examples: We have repeated the test several times.; We have seen the same problem again.; The supplier has already checked the module once.
Common pitfall + fix: Don’t use present perfect with finished time markers like yesterday. — Use it with “since”, “so far”, “recently”.

3️⃣ First conditional for consequences

Rule: Use “if” + present simple + “will” to describe real future consequences of a present situation.
Examples: If we don’t find the root cause, we will have to delay delivery.; If the module overheats again, the simulator will shut down.; If the test fails, we will repeat it tomorrow.
Common pitfall + fix: Many learners use “will” in both parts. — Keep “will” only in the result clause, not in the “if” part.

4️⃣ Modals of obligation: have to / need to

Rule: Use “have to” or “need to” to express external or strong obligation in professional contexts.
Examples: We have to delay the schedule if tests fail.; We need to explain the situation clearly to the client.; The supplier has to support us during the test campaign.
Common pitfall + fix: Learners sometimes use “must” too often. — In business English, “have to” and “need to” sound more neutral and polite.

✍️ Vocabulary

  battery failure

Meaning: a situation where a battery stops working correctly or loses power suddenly.
Synonyms: battery fault, power failure, malfunction
Chunk/Idiom: investigate the battery failure
Example: We had to stop the session because of a sudden battery failure.
Morphology: noun phrase; noun + noun compound
Self-practice: Describe a time when you saw a battery failure in your own devices.

  simulator

Meaning: a machine or program that imitates a real system for training or testing.
Synonyms: training system, mock-up, test rig
Chunk/Idiom: run a scenario on the simulator
Example: The simulator shut down in the middle of a critical training scenario.
Morphology: noun; countable; engineering term
Self-practice: Write two sentences about what your simulator can do in training.

  prototype

Meaning: the first version of a product that is used for testing before mass production.
Synonyms: first version, pilot model, test unit
Chunk/Idiom: qualify the prototype with the authorities
Example: The prototype had worked perfectly for months in earlier tests.
Morphology: noun; often used in engineering and design
Self-practice: Explain how a prototype is different from the final series product.

  root cause

Meaning: the main underlying reason why a problem or failure happens.
Synonyms: main cause, underlying reason, source of the problem
Chunk/Idiom: find the root cause of the failure
Example: We must find the root cause before we restart the test campaign.
Morphology: noun phrase; root used as an adjective before a noun
Self-practice: List three questions you ask to find the root cause of an issue.

  retrofit schedule

Meaning: the planned dates and order for upgrading existing equipment with new parts.
Synonyms: upgrade plan, modification timeline, project schedule
Chunk/Idiom: delay the retrofit schedule for the client
Example: If tests fail again, we will have to delay the retrofit schedule.
Morphology: noun phrase; retrofit as noun + noun
Self-practice: Describe how a retrofit schedule can affect your customer’s operations.

  test campaign

Meaning: a planned series of tests carried out to validate a product or system.
Synonyms: test program, validation phase, qualification plan
Chunk/Idiom: run a long test campaign on the new battery
Example: The test campaign is still running while the supplier investigates the issue.
Morphology: noun phrase; test + noun used for engineering projects
Self-practice: Outline a short test campaign for checking a new component at work.

☁️ Examples (+ audio)

🔊 Play We discovered a serious battery failure during yesterday's simulator test.

🔊 Play Since then we have repeated the test several times with the new prototype.

🔊 Play If we don't find the root cause, we will have to delay delivery.

🔊 Play We need to explain clearly to the client why the system failed.

✏️ Exercises

Grammar

Vocabulary & Comprehension

✅ Guided practice

Mini-dialogue:

A: We discovered a serious battery failure during yesterday's long simulator test.
B: How will this affect the retrofit schedule for our client?
A: If we solve the problem this week, we will still deliver on time.

Why this matters:

Clear explanations of technical failures help clients stay calm, trust your team, and understand realistic timelines.

Verb & Adjective Pack:

investigate — We must investigate why the module overheated so quickly.
repeat — We will repeat the test campaign with the updated configuration.
reliable — The client expects a reliable simulator for every training session.
delayed — The project is delayed because the battery failed in several tests.

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