Licensed technicians · Written estimates
Vehicle Diagnostics & Dash Lights
Diagnosis is the part of the job most shops charge for and most customers do not see. What you are paying for is the time it takes to prove which component has failed, so that the repair you approve is the repair that fixes the car. We would rather spend an extra hour testing than have you back in two weeks with the same complaint.
We handle the full range of dash warnings: check engine, ABS, traction control, airbag, battery, TPMS, brake and the increasingly common driver-assist faults on newer vehicles. Where a fault is intermittent, we record data over time instead of guessing from a static code.
What this service covers
- Full-system scan — engine, transmission, ABS, SRS, body and network modules
- Live data and freeze-frame analysis
- Electrical circuit testing with a meter and scope
- Charging and starting system testing
- Parasitic draw testing for batteries that go flat overnight
- Post-repair verification drive and re-scan
- A written explanation of the fault, the test result and the fix
Signs it is time to book
- Any dash warning light that stays on after startup
- A battery that keeps going flat with no obvious cause
- Intermittent stalling, hesitation or a no-start that comes and goes
- Electrical gremlins — flickering lights, windows or accessories
- Dash warnings that appear only in the cold or only in the wet
- A car that failed an inspection elsewhere on a code nobody could explain
Every job starts with an inspection and a written estimate. Nothing gets done without your approval — call (705) 748-4223 or drop the vehicle at 485 Parkhill Rd E, Peterborough, Ontario K9L 1C2.
Vehicle Diagnostics & Dash Lights — the questions we get asked most
- What does a diagnostic actually cost?
- We quote diagnostic time up front based on the complaint. A single stored code on a common platform is quick; a wiring fault that only appears at −18 °C on a wet morning is not. You approve the diagnostic time before we start, and we tell you what we found either way.
- Why do you charge for diagnosis when the code is free elsewhere?
- Pulling a code takes ninety seconds and tells you which circuit complained. Proving what caused it takes testing, wiring diagrams and experience. The free read is the first sentence of the story, not the ending.
- My battery keeps dying overnight. What causes that?
- Either the battery no longer holds charge, the alternator is not replacing it, or something is drawing current after the car sleeps — a stuck relay, an aftermarket accessory, a module that never powers down. Parasitic draw testing separates those three, and we do it as a measured test rather than a guess.
- Can you clear the light without fixing anything?
- We can clear a code, but if the underlying fault is still present it will come back within a few drive cycles. We will not clear a light to disguise a problem before a sale or an inspection.
- Why do warning lights appear when it gets cold?
- Cold changes everything — battery voltage drops, plastic connectors contract, marginal sensors go out of range, and tire pressure falls about 1 psi for every 5 °C. Around here a whole category of faults is seasonal, which is useful diagnostic information in itself.
- Do you have the equipment for newer vehicles?
- Yes, including bidirectional scan capability and module-level access on most current platforms. If a repair requires a factory-only programming step that we cannot perform, we tell you before you spend money, not after.
- The light went off by itself. Should I still bring it in?
- Worth a scan. The stored history and pending codes remain in memory even after the light clears, and an intermittent fault caught early is much cheaper than the failure it becomes.
- Can a diagnostic tell me whether a used car is worth buying?
- It is a large part of a pre-purchase inspection. A full-system scan reveals cleared codes, module history and readiness monitors that were recently reset — often the most honest thing a used car will tell you.
Where we provide vehicle diagnostics & dash lights
The shop is at 485 Parkhill Rd E, Peterborough, Ontario K9L 1C2, and drivers come to us from across the region. Read how this work applies where you drive:
- Peterborough drivers
- Lakefield drivers
- Otonabee-South Monaghan drivers
- Millbrook drivers
- Norwood drivers
- Lindsay drivers
Related services at 4 Aces Auto Center
Google reviews
What our customers say
“Very efficient in repairs even in difficult repairs. They try there best to get the vehicle on the road as fast as they can. Greatful to have a good repair shop to have my vehicle in good repair. Thank you for all your good work.”
“I needed a quick fix on my truck as I am a contractor and needed vehicle. I called 4 Aces and Chris got me in the next buisness day 1st thing in the morning. Was met with Smiles and coffee and excellent service. They had me fixed up and back on site the same morning. 5 Star Service at 4 Aces👍”
“They're awesome. After the bs I've been through with other garages and my car, it was a breathe of fresh air with these guys. Anytime no contact drop off, quick workers and chill as well. I'll be going back!”
“The staff at Four Aces was friendly and efficient. They addressed my problems immediately and had me back on the road in good time after checking the vehicle over for any other issues and reporting the results directly to me. Thank you for your continued service and caring in keeping my vehicle in good and safe shape.”
“I have been very pleased with the service I have received at 4 Aces Automotive Centre. They have solved problems that other facilities were not able to do. The pricing seems fair—certainly comparable to other centres. And they seem very friendly, knowledgable, efficient, and skilled. Once, when they had my car up on the hoist—performing a repair— they detected an additional—and serious—problem. Rather than just telling me what they had found, they took me out into the garage to show me the issue and suggested that I have an auto body expert look at the problem to determine if it could be safely resolved before I had 4 Aces proceed with some additional repairs. I trust their work and they seem to genuinely care about the safety of my vehicle.”
“Very efficient in repairs even in difficult repairs. They try there best to get the vehicle on the road as fast as they can. Greatful to have a good repair shop to have my vehicle in good repair. Thank you for all your good work.”
“I needed a quick fix on my truck as I am a contractor and needed vehicle. I called 4 Aces and Chris got me in the next buisness day 1st thing in the morning. Was met with Smiles and coffee and excellent service. They had me fixed up and back on site the same morning. 5 Star Service at 4 Aces👍”
“They're awesome. After the bs I've been through with other garages and my car, it was a breathe of fresh air with these guys. Anytime no contact drop off, quick workers and chill as well. I'll be going back!”
“The staff at Four Aces was friendly and efficient. They addressed my problems immediately and had me back on the road in good time after checking the vehicle over for any other issues and reporting the results directly to me. Thank you for your continued service and caring in keeping my vehicle in good and safe shape.”
“I have been very pleased with the service I have received at 4 Aces Automotive Centre. They have solved problems that other facilities were not able to do. The pricing seems fair—certainly comparable to other centres. And they seem very friendly, knowledgable, efficient, and skilled. Once, when they had my car up on the hoist—performing a repair— they detected an additional—and serious—problem. Rather than just telling me what they had found, they took me out into the garage to show me the issue and suggested that I have an auto body expert look at the problem to determine if it could be safely resolved before I had 4 Aces proceed with some additional repairs. I trust their work and they seem to genuinely care about the safety of my vehicle.”
Book vehicle diagnostics & dash lights
Tell us what the vehicle is doing and we will book the inspection, measure it properly and quote from the result. Drop-offs welcome at 485 Parkhill Rd E, Peterborough, Ontario K9L 1C2.
485 Parkhill Rd E, Peterborough, Ontario K9L 1C2 · Mon – Fri 8:00 – 5:00