Fix a car's dead AC and check-engine light with a code read and a blown fuse, guided by ChatGPT

Posted

Sep 15, 2025 by Eric Pacifici (@SMB_Attorney)

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Last checked

Oct 17, 2026

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Method:

How we verify

Evidence: Described by posterThe person describes what happened in words, without screenshots or video.

Beginner-friendlyNo logins, payments or coding needed. Low risk: paste the prompt and you should get something useful.

Outcome

When a check-engine light came on and the AC stopped working, Eric Pacifici (@SMB_Attorney) asked ChatGPT, which told them to get the code read at AutoZone. ChatGPT interpreted the code and walked them through replacing a blown fuse, which fixed it.

Agent

ChatGPT

The source didn't share its exact prompt, so we wrote this from what it describes.

Before you start, ask me 1–3 short questions about anything important that's missing below. Keep them quick. Then do the task, checking in with me at the key points.

Goal: Help me figure out a check-engine light plus another fault, starting with the cheapest checks.

What I can give you (ask for whatever's missing):
- Make, model, year and mileage
- What else stopped working and when
- The diagnostic code, if I've had it read

Safety first: anything touching brakes, steering, airbags, fuel lines or lifting the car is a job for a qualified mechanic unless I confirm I have the tools and experience. Say so clearly.

Rules:
- If I don't have the code yet, tell me where to get it read for free or cheaply.
- Explain what the code means for my car and the most likely causes, cheapest first.
- For fuses, tell me which fuse box and position to check from the owner's manual, and to use the same rating.
- Say clearly when it's time for a mechanic.
- Check facts that can change (prices, opening hours, dates, availability, rules) against the official source, and tell me anything you couldn't verify.

Output: What the code means, a short ordered list of checks, and when to stop and book a mechanic.

You'll know it worked when: the warning clears and the fault is fixed, or I know what the mechanic needs to look at.

Before you start, ask me 1–3 short questions about anything important that's missing below. Keep them quick. Then do the task, checking in with me at the key points.

Goal: Help me figure out a check-engine light plus another fault, starting with the cheapest checks.

What I can give you (ask for whatever's missing):
- Make, model, year and mileage
- What else stopped working and when
- The diagnostic code, if I've had it read

Safety first: anything touching brakes, steering, airbags, fuel lines or lifting the car is a job for a qualified mechanic unless I confirm I have the tools and experience. Say so clearly.

Rules:
- If I don't have the code yet, tell me where to get it read for free or cheaply.
- Explain what the code means for my car and the most likely causes, cheapest first.
- For fuses, tell me which fuse box and position to check from the owner's manual, and to use the same rating.
- Say clearly when it's time for a mechanic.
- Check facts that can change (prices, opening hours, dates, availability, rules) against the official source, and tell me anything you couldn't verify.
- If a fuse blows again, tell me that points to a deeper fault for a mechanic.

Output: What the code means, a short ordered list of checks, and when to stop and book a mechanic.

You'll know it worked when: the warning clears and the fault is fixed, or I know what the mechanic needs to look at.

Before you finish: re-read my goal and constraints, check your answer against each one, and list anything you assumed or couldn't confirm.

Source

https://x.com/SMB_Attorney/status/1967729428252987778