Check-engine & electrical diagnostics · Charlotte, NC

Read the code. Find the cause. Fix it once.

A code only tells us which system to test. Our technicians test until they find the part that actually failed — then show you the readings and the price before anything is replaced.

Book a diagnosis · $149 Look up a code

ASE Master-certified technicians
$149 diagnosis, credited to the repair
4.9 from 870 reviews · 24-month / 24,000-mile warranty

Live data · Bay 2

Recording

CH1 · Engine RPMCH2 · O2 sensor, before the catalystCH3 · O2 sensor, after the catalyst

RPM: 0812
O2 · B1S1: 0.72 V
O2 · B1S2: 0.65 V
Fuel trim: +2.1%

Healthy engineThe upstream oxygen sensor switches rich and lean about once a second while the downstream one holds steady — the catalyst is doing its job.P0300 · MisfireEach dip in RPM is a cylinder that did not fire: the crankshaft slows for a moment and the upstream sensor sees a gulp of unburned air.P0171 · LeanThe upstream sensor sits low and fuel trim climbs past +15% as the computer adds fuel for air it never measured.P0420 · CatalystThe downstream sensor now copies the upstream one: the converter has stopped storing oxygen, and the exhaust leaves dirtier than it should.

The upstream oxygen sensor switches rich and lean about once a second while the downstream one holds steady — the catalyst is doing its job.

Codes read this year · 4,812Average diagnosis · 74 minComebacks · 0.8%$149 diagnosis · credited to the repairASE Master-certifiedNight drop · open 24/7Hybrid & EV qualifiedFree shuttle · 5 milesCodes read this year · 4,812Average diagnosis · 74 minComebacks · 0.8%$149 diagnosis · credited to the repairASE Master-certifiedNight drop · open 24/7Hybrid & EV qualifiedFree shuttle · 5 miles

CH 01//What we diagnose

Eight channels. One method.

Whatever lit up, the method is the same: save the data, test the circuit, prove the part — and only then put a price on the repair.

01
Check-engine light
Codes read, freeze-frame and live data saved, then pinpoint tests until the failed part is proven. The fee comes off the repair.
$149 · 60–90 min
02
Electrical faults
Dead circuits, fuses that keep blowing, lights and gauges that come and go — traced with the wiring diagram and a scope.
$149 first hour
03
Battery drain & no-starts
A parasitic-draw test that finds the module keeping your car awake at night, with starter and charging checks.
$129 · overnight test
04
ABS, traction & airbag lights
Wheel-speed sensors, modules and wiring tested with the system’s own data; airbag faults handled to the factory procedure.
$149 · 60–90 min
05
Rough idle, stalls & hesitation
Misfires, vacuum leaks, fuel pressure and sensors — tested when the problem shows up, with a data logger on the road.
$149 · about 90 min
06
Emissions inspection failures
Failed the state emissions inspection? We read the readiness monitors, fix the cause and run the drive cycle so you pass.
$149 · credited
07
Module programming & keys
Replacement modules programmed and set up with factory-level software; lost keys and fobs paired to the car.
From $180 · 1–2 hr
08
Hybrid & EV systems
High-voltage battery health, inverter and cooling faults, and the 12-volt problems that stop an EV from waking up.
$189 · about 90 min

CH 02//Trouble-code lookup

What is your car trying to tell you?

Type the code from a scan — or pick one of the twelve we see most — for a plain-English meaning, the usual causes and how soon to come in.

Enter a trouble code

>Decode

Codes are a letter and four characters, like P0420. Any well-formed code gets decoded.

Or pick one

P0300Random or multiple cylinder misfireStop driving
One or more cylinders are not firing properly, so the engine runs rough and unburned fuel reaches the exhaust. If the check-engine light is flashing, the catalytic converter is being damaged as you drive.
Worn spark plugs or ignition coils; a vacuum leak; low fuel pressure or a clogged injector; low compression in a cylinder
P0420Catalytic converter efficiency below thresholdBook soon
The oxygen sensor after the catalytic converter reads almost the same as the one before it, so the converter is no longer cleaning the exhaust as it should. You will fail an emissions inspection.
An aging catalytic converter; a faulty downstream oxygen sensor; an exhaust leak near the sensors; a misfire that overheated the converter
P0171System too lean, bank 1Book soon
The engine is getting more air than the computer can account for, so it keeps adding fuel to make up for it. Left alone it brings hesitation, misfires and hard starts.
A vacuum or intake leak after the airflow sensor; a dirty mass airflow sensor; a weak fuel pump or clogged filter; a split PCV hose
P0442Small leak in the fuel-vapour systemDrive on
The system that traps fuel vapour from the tank has found a small leak. The car drives normally, but it will fail an emissions inspection and you may smell fuel.
A worn gas-cap seal; a cracked vapour hose; a sticking purge or vent valve; a leaking charcoal canister
P0128Engine slow to reach temperatureDrive on
The engine is taking too long to warm up, usually because the thermostat is stuck open. Expect weak cabin heat and worse fuel economy, especially in winter.
A thermostat stuck open; a faulty coolant temperature sensor; low coolant; a cooling fan that runs all the time
P0700Transmission control system faultBook soon
The transmission computer has stored a fault of its own and asked for the light. The detailed code lives in the transmission module, and the gearbox may be in limp mode with fewer gears.
A transmission sensor or solenoid fault; low or burnt transmission fluid; damaged wiring or a connector; an internal transmission problem
U0100Lost communication with the engine computerStop driving
The other computers in the car cannot hear the engine computer on the network. The car may stall, refuse to start or light up the whole dashboard.
A weak battery or a poor ground; a damaged network wire or connector; a blown fuse feeding the module; a failed engine computer
B1000Body control module internal faultDrive on
The module that runs your lights, locks and wipers has stored an internal fault. On many makes a low-voltage start sets it and it clears once the cause is fixed; on others the module needs an update or replacing.
Low battery voltage during a start; water in the module or its connector; software that needs an update; a failed module
C0035Left front wheel-speed sensor circuitBook soon
The ABS computer has lost a clean signal from the left front wheel. The ABS and traction lights come on and those systems switch off: the brakes still work, but will not stop a skid.
A damaged sensor or its wiring; rust lifting the sensor; a worn wheel bearing with a magnetic ring; debris on the tone ring
P0455Large leak in the fuel-vapour systemDrive on
The fuel-vapour system has found a large leak — very often a gas cap left loose. Tighten it, and the light may go out after a few days of driving.
A missing or loose gas cap; a disconnected vapour hose; a vent valve stuck open; a cracked filler neck
P0507Idle speed higher than expectedBook soon
The engine idles faster than the computer is asking for, so extra air is getting in somewhere. You may notice a high idle at lights and a harder push on the brake pedal.
A vacuum leak; a dirty or failing throttle body; a leaking intake gasket; an idle relearn skipped after a battery change
P0562System voltage lowStop driving
The computer sees less than about eleven volts with the engine running, so the battery is not being charged. If the alternator has failed, the car runs until the battery is flat — then stalls.
A failing alternator; a slipping or broken drive belt; a corroded battery cable or ground; a battery at the end of its life

P0300

Random or multiple cylinder misfire

PPowertrain
0Generic code
3Ignition & misfire
00Fault number

What it means

One or more cylinders are not firing properly, so the engine runs rough and unburned fuel reaches the exhaust. If the check-engine light is flashing, the catalytic converter is being damaged as you drive.

Likely causes

Worn spark plugs or ignition coils; a vacuum leak; low fuel pressure or a clogged injector; low compression in a cylinder

How urgent

Drive onBook soonStop driving

A flashing check-engine light, a hot engine or a sudden loss of power always means stop and call.

Book a diagnosis for P0300 · $149

CH 03//How a diagnosis runs

Four sectors. No guesswork.

S1
10 min
Interview & scan
You tell us when it happens. We scan every module and save the freeze-frame data from the moment the light came on.
S2
45 min
Pinpoint tests
Scope, smoke machine, pressure gauges and the wiring diagram — testing until one part is proven to have failed.
S3
10 min
Report & price
A text with the readings, the photos and a fixed price for the repair. Nothing happens until you approve it.
S4
Same day
Repair & verify
The repair, a road test with a data logger, codes cleared and readiness monitors checked before you collect.

CH 04//Why Pitlane

No parts cannon.

A code tells us which system to test, not which part to buy. Replacing parts until the light goes out is how a $90 fix becomes a $900 afternoon. We test first, show you the proof, and price the repair before we touch it — and if the same fault comes back, so do we.

A technician testing the fuse box with a scan tool

$149Diagnosis, creditedComes off the repair when we fix it
0.8%Comebacks last yearCars back for the same fault
24 moParts & labor warrantyOr 24,000 miles, in writing
74 minAverage diagnosisFrom scan to written report

CH 05//Rate card

Every rate, posted.

Most booked

Check-engine diagnosis

$149credited to the repair

Every module scanned
Freeze-frame and live data saved
Pinpoint tests until the fault is proven
A written report with the readings
A fixed price for the repair

Have us do the repair and the $149 comes off the invoice.

Book a diagnosis

ServiceRate

Check-engine diagnosisScan, freeze-frame, pinpoint tests, written report$149
Electrical diagnosisFirst hour, wiring diagrams and scope$149
Further diagnostic timeQuoted and approved before we continue$38 per 15 min
Battery-drain testOvernight parasitic-draw test$129
Smoke testFinds the leak behind P0442 and P0455$119
Pre-purchase scanEvery module scanned, report in an hour$129
Module programmingFactory-level software, per modulefrom $180
Hybrid battery healthCell-by-cell report with a printout$189
Emissions retest supportDrive cycle and readiness after our repairFree

Prices in US dollars before tax. Further diagnostic time is always quoted and approved before we continue; you never pay for testing you did not agree to.

CH 06//Driver reports

Fixed once. Logged.

4.9

★★★★★

Average from 870 Google reviews

Log 01Darnell W.Resolved

2015 Ford F-150 · P0171 lean code

Two shops sold me sensors. Pitlane smoke-tested it, found a split intake boot in twenty minutes and showed me the fuel trims before and after. $149 and a $40 part.

Log 02Kim T.Resolved

2018 Honda Accord · battery drain

My battery was dead every Monday. They ran an overnight draw test and found the trunk module staying awake. Fixed once, and it has stayed fixed.

Log 03Rosa M.Resolved

2012 Toyota Prius · hybrid warning

They printed a cell-by-cell report on my hybrid battery and told me it had years left in it. Saved me from a very expensive mistake.

Log 04Ethan B.Resolved

2016 Chevrolet Silverado · U0100

Stalling, every light on the dash. It was a corroded ground behind the engine — and they sent me the scope trace to prove it.

CH 07//The crew

Three technicians. Zero guesses.

Tech 01

Andre Mitchell

Owner · ASE Master Technician, L1

Twelve years on dealership drivability problems before he opened Pitlane. Andre writes every diagnostic report himself, and signs it.

Tech 02

Jess Romero

Electrical lead · ASE certified, A6 & A8

Reads a wiring diagram like a road map. Jess runs the battery-drain tests and the network faults that send other shops in circles.

Tech 03

Sam Okoye

Hybrid & EV technician · high-voltage trained

Works on the cars with orange cables: hybrid battery reports, inverter faults and the 12-volt problems that keep an EV asleep.

CH 08//Locate

Off the interstate, on Dynamo Way.

1820 Dynamo Way, Charlotte

Hours this week

Monday7:00 am – 6:00 pm
Tuesday7:00 am – 6:00 pm
Wednesday7:00 am – 6:00 pm
Thursday7:00 am – 6:00 pm
Friday7:00 am – 6:00 pm
Saturday8:00 am – 1:00 pm
SundayClosed

Night dropKey box beside bay 1, open around the clock.
Waiting roomWi-Fi, coffee, and a screen where we show you the readings.
ShuttleFree rides within five miles, 8 am to 5 pm.

CH 09//Questions

Asked at the counter

Q1The parts store read my code for free. Why pay $149?

A free code read tells you what the computer noticed, not what failed. P0171 can be a $6 hose or a $400 fuel pump; the $149 buys the testing that tells them apart — and it comes off the repair.

Q2Is it safe to drive with the check-engine light on?

If it is steady and the car drives normally, usually yes — book within a week or two. If it is flashing, or the car runs rough, overheats or loses power, pull over and call us: a flashing light is a misfire that can destroy the catalytic converter.

Q3Will you clear the code?

Only after the repair is proven. Clearing a code without fixing the cause erases the freeze-frame data we need and resets the readiness monitors an emissions inspection checks.

Q4Why did my light come back after another shop cleared it?

Because clearing a code is not a repair. The computer re-runs its self-tests over a few drives, finds the same fault and turns the light back on.

Q5How long does a diagnosis take?

Most check-engine diagnoses take 60 to 90 minutes. Intermittent electrical faults and battery drains can take longer, and we always call before going past the time you approved.

Q6Do you work on hybrids and electric cars?

Yes. Sam is trained for high-voltage safety, and we have the tools to read hybrid battery health and electric-car module data.

Q7What if you cannot find the problem?

If we cannot prove the cause in the time you approved, you pay only for that time and get every reading we took — so nothing is wasted if you want a second opinion.

CH 10//Book a diagnosis

Tell us what the car is doing.

When does it happen — cold or warm, at idle or on the highway? Any codes you already have? We call back within the hour to book a bay. Diagnosis is $149, credited to the repair.

Call: (704) 555-0102
Email: bay@pitlanediagnostics.example
Shop: 1820 Dynamo Way, Charlotte
Hours: Mon–Fri 7:00–6:00 · Sat 8:00–1:00

Diagnosis requestChannel open