Check Engine Light and Readiness Monitor Explainer

Turns the scan results, trouble codes, readiness monitor status, and technician notes from a smog check into a clear, honest explanation the customer can follow.

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Before and after

BEFORE · what the owner typed

Silverland Smog Check, 967 Reedland Ave, Doveford. Customer Thelma Ramirez, 2013 Toyota Sienna white, 131,420 miles. Tech is Terrence Porter. MIL on. Test result FAIL. Codes: P0171 system too lean bank 1, P0420 cat efficiency below threshold bank 1. Terrence found cracked intake boot, rec replace, thinks that's the lean code. Cat: downstream sensor looks slow, needs more diag before we say cat is bad. Monitors ready: misfire, fuel system, comprehensive components, catalyst, O2 sensor, O2 heater. Not ready: EVAP. Customer said battery replaced last week, Terrence thinks that's why EVAP not ready. Air filter dirty. Prices: intake boot replacement $142.50, cat diagnosis $120.00, air filter $38.00. Retest after repairs.

AFTER · what the skill produced

Hi Thelma, thanks for bringing in your white 2013 Toyota Sienna (131,420 miles). Here is what we found today.

Your result: The smog test result today was a fail, and your check engine light is on.

What the codes mean:

P0171: The engine is getting too much air compared to fuel on one side. Terrence found a cracked intake boot, which is the rubber piece that carries air into the engine. We believe this is the cause of this code.
P0420: The catalytic converter, the part that cleans your exhaust, is reporting lower efficiency than it should. Terrence saw that the sensor after the converter looks slow. The cause has not been confirmed yet, so we recommend more diagnosis before anyone says the converter itself is bad.

Your readiness monitors: Monitors are self-checks your car's computer runs on each system. We checked 7. 6 are ready and 1 is not ready.

Ready: misfire, fuel system, comprehensive components, catalyst, O2 sensor, O2 heater
Not ready: EVAP (the fuel vapor system). You told us the battery was replaced last week, and Terrence noted that this may be why the EVAP self-check has not finished.

Recommended now

Replace the cracked intake boot, for the P0171 code and the check engine light: $142.50
Catalytic converter diagnosis, to confirm the cause of P0420: $120.00
Total for this group: $262.50

Also recommended

Engine air filter is dirty. We recommend replacing it: $38.00
Total for this group: $38.00

Total for everything recommended: $300.50

Next step: We recommend starting with the intake boot and the converter diagnosis, then bringing the Sienna back to Silverland Smog Check for a retest. If you want to approve only some of these items, just tell us, and we will note anything you decline as your decision.

Questions for the owner

What is the retest fee, if any, and how long does the customer have to come back?
Does Thelma have a registration deadline we should mention?
Do you want to give her any instructions for getting the EVAP monitor to finish, and if so, what are they?
Please confirm locally whether a not ready monitor affects the result in your area before telling the customer.

What it does

Turns the scan results, trouble codes, readiness monitor status, and technician notes from a smog check into a clear, honest explanation the customer can follow. It covers why the check engine light is on, what each code means, which monitors are ready or not ready, and what the shop recommends next.

Use it when: Use when a smog check shop needs to explain a check engine light, trouble codes, or readiness monitor status to a customer, such as: explain these codes to the customer, why did my car not pass, what does not ready mean, or write up this smog result.