Complete Car Electrical Service in Ambattur, Chennai
Electrical faults are the hidden reason many car AC problems go unsolved. GM Car A/C Service diagnoses AC circuit faults, battery and alternator problems, starter faults, dashboard warnings and wiring issues for all car brands.
Electrical faults need precise diagnosis, not guesswork. Call us — we find the exact fault, not just swap parts randomly.
Get Your Electrical Fault Diagnosed
+91 8428000085 WhatsApp for QuoteMon–Sat 10AM–8PM
FREE Car Electrical Checkup
Battery, alternator, starter & wiring scan — at no charge. We diagnose before we replace; any repair is quoted transparently for your approval, with zero obligation.
Claim Free Checkup Book on WhatsAppWhy is my car AC not working even after gas was refilled?
If your car AC was recharged with refrigerant but still doesn't cool, the fault is almost certainly electrical. Many workshops only check and fill gas — they don't diagnose electrical faults. This is why some customers come to us after spending money elsewhere with no result.
Common AC electrical faults we find and fix:
- Failed AC compressor relay — prevents compressor from receiving power
- Blown AC fuse — easy to replace when the right fuse is identified
- Faulty AC pressure switch — incorrectly signals low pressure, blocking compressor
- Failed blower motor or resistor — no airflow despite AC being on
- Wiring harness damage — rodent damage, heat damage, chafed insulation
- AC control module fault — signals not sent or received correctly
Call +91 8428000085 — we diagnose the exact electrical fault before recommending any repair.
Diagnosis before parts: the inspection and testing scope is confirmed before work starts. If repair is recommended, GM explains the test result, parts, labour, warranty terms and estimate for your approval.Auto Electrical Services We Offer
AC Electrical Circuit Diagnosis
Full diagnosis of the AC electrical system — compressor relay, pressure switches, blower motor circuit, AC control module, wiring continuity testing.
Battery & Alternator Testing
Battery load testing, cold cranking amp verification, alternator output voltage and current testing. Chennai's heat degrades batteries fast — we check before they fail.
Wiring & Fuse Diagnosis
Systematic tracing of wiring faults — shorts, open circuits, rodent damage, corroded connectors, blown fuses and their root causes. We find the fault, not just replace the fuse.
Electrical Symptoms We Diagnose
AC compressor not engaging / clutch not clicking
The compressor clutch not engaging is often electrical — failed relay, blown fuse, faulty pressure switch, or low voltage. Our technicians test each component in sequence to identify the exact failure point before any parts are replaced.Blower fan not working or working on only some speeds
A fan that works on high but not low speeds usually indicates a failed blower resistor (common in Chennai's heat). A completely dead blower points to a failed motor, fuse, or relay. We test and replace only the faulty component.Car battery draining overnight
Parasitic battery drain — where something stays on after the car is switched off — requires systematic current draw testing on each circuit. We use a clamp meter to identify the circuit drawing abnormal current, then trace it to the specific component.AC working intermittently — cooling on and off
Intermittent AC faults are the hardest to diagnose — they disappear when you bring the car in. Our technicians know the common intermittent failure patterns: heat-sensitive relays, corroded connectors that make contact only sometimes, and pressure switch faults that cut out under load.Rat bite / rodent damage to car wiring
Rat and rodent bites on wiring are a very common cause of sudden electrical faults in Chennai — AC cutting out, warning lights, a dead sensor, or a circuit that stops working overnight. We trace the chewed wiring harness, repair or replace the damaged section, restore proper insulation and connectors, and test the circuit end to end. We fix the actual bitten wiring, not just clear the fault code.Function keys / buttons / switches not working
Dashboard buttons, AC control panel keys, power window switches, wiper or light controls that stop responding are usually a failed switch, a broken connector, or a wiring fault behind the panel. We test each control, find whether the fault is the switch itself or the circuit feeding it, and repair or replace only the faulty part so every function key works again.The GM Diagnostic Difference
We don't guess and replace parts hoping to fix the fault. Every diagnosis starts with systematic testing using proper tools — multimeters, circuit testers, and manufacturer wiring diagrams. You only pay for what actually needs replacing.
vehicles served since 2019
Diagnosis-first · written estimate before work
+91 8428000085 WhatsApp Us
Electrical Symptom Quick Reference
| Symptom | Possible cause | Recommended check |
|---|---|---|
| Battery warning light stays on while engine runs | Alternator not charging, worn brushes, failed diode, loose or corroded connection | Alternator output voltage test at idle and higher RPM |
| Car cranks slowly or does not start | Weak or discharged battery, corroded terminals, poor earth connection, starter fault | Battery load test and terminal/earth inspection |
| AC blows warm air though gas level is normal | Failed compressor relay, blown AC fuse, faulty pressure switch, wiring fault | AC electrical circuit and relay test |
| Function keys, switches or dashboard buttons stop responding | Failed switch, broken connector, wiring fault behind the panel | Continuity test of the switch and its wiring |
| Several electrical faults appear suddenly together | Rodent-damaged wiring harness, chafed insulation, blown fuse | Visual harness inspection and circuit continuity test |
| Battery drains overnight with no visible cause | Parasitic current draw from a stuck-on circuit or faulty component | Clamp-meter parasitic draw test with circuits isolated one by one |
| Blower fan works on some speeds only | Failed blower resistor or partially failed motor | Blower circuit and resistor test at each speed |
This table lists common patterns for reference. It does not diagnose your specific vehicle — a technician confirms the actual cause after inspection.
What Affects Auto Electrical Repair Cost
The cost of auto electrical repair depends on the vehicle model, the brand and specification of the replacement part needed, how much labour is required to access and test the affected circuit, whether other components were damaged by the original fault, and parts availability for that specific car. It also depends on whether the failure is in the component itself — a relay, sensor or motor — or in the wiring feeding it, since wiring faults typically take more diagnostic time. An estimate is given only after the fault is diagnosed.
Diagnose Your Car's Electrical Fault Today
Stop guessing and swapping parts. At GM Car A/C Service, we use systematic diagnostic methods to find the exact fault — then repair only what's needed.
Precise. Honest. Reliable. Since 2019.
12A, Gangai Amman Kovil Street, Kallikuppam, Ambattur, Chennai 600053 · Mon–Sat 10AM–8PM
Get Your Free 30-Point Checkup
We reply in workshop hours · No spam
Every GM Cool Care plan includes A/C and electrical checkup support. Compare plans.
Frequently Asked Questions — Auto Electrical Service
Pricing: Free 30-point A/C & electrical checkup — ₹0, no purchase required — covers the initial electrical fault diagnosis. Any repair found necessary is quoted only after the fault is confirmed; there is no fixed price list for electrical repairs since parts and labour vary by fault and vehicle.
Do you service electric vehicles (EVs)?
We service the AC and general electrical systems of electric and hybrid vehicles — cabin cooling, wiring and diagnostics. High-voltage battery and drivetrain work needs the vehicle manufacturer's own service network. Call +91 8428000085 to confirm we can help with your EV model.Why is my car AC not working after gas filling?
If gas was refilled but AC still doesn't work, the fault is electrical — failed relay, blown fuse, pressure switch fault, or blower motor problem. GM Car A/C Service diagnoses AC electrical circuits systematically to find the exact failed component.Can a weak battery cause car AC problems?
Yes. Voltage drop from a weak battery affects compressor engagement, blower motor speed, and control module function. Battery health testing is part of our AC diagnostic process whenever electrical symptoms are present.How long does auto electrical diagnosis take?
Focused auto electrical diagnosis typically takes 30–90 minutes. Simple relay or fuse repairs are short jobs. Complex wiring fault tracing may take longer. We provide a clear timeline and estimate before work begins.What is the cost of auto electrical service in Chennai?
Cost depends on the fault type and components involved. Simple fuse or relay replacement is very affordable; wiring repairs or module replacements vary. GM Car A/C Service provides transparent quotes before any work. Call +91 8428000085 for your estimate.Do you repair rat bite / rodent damage to car wiring?
Yes — rat and rodent bites on wiring are a very common cause of sudden electrical faults in Chennai. We trace the chewed wiring harness, repair or replace the damaged section, restore insulation and connectors, and test the circuit end to end. We fix the actual bitten wiring, not just clear the fault code.My car's function keys / buttons / switches are not working — can you fix it?
Yes. Dashboard buttons, AC panel keys, power window switches, wiper and light controls that stop responding are usually a failed switch, broken connector, or wiring fault behind the panel. We test each control, find whether the switch or the circuit is at fault, and repair or replace only the faulty part so every function key works again.What tools do you use to diagnose electrical faults?
GM Car A/C Service uses multimeters, clamp meters for current-draw testing, circuit testers and, where relevant, an OBD scanner to check stored fault codes. Wiring diagrams for the specific make and model are used to trace circuits accurately rather than guessing at components.Can electrical faults come back after repair?
A properly diagnosed and repaired electrical fault should not recur from the same cause. If a similar symptom returns, it is usually a different component in the same circuit — bring the vehicle back so the circuit can be re-tested rather than assuming the earlier repair failed.Last reviewed: 26 July 2026 · Technical review: G.M. Manigandan, founder, Managing Director and lead technician
Frequently asked questions
Why is my car AC not working even after gas filling?
If your car AC was recharged but still doesn't work, the fault is likely electrical. Common causes include a failed AC compressor relay, a blown fuse in the AC circuit, a faulty AC pressure switch, a failed blower motor, or a wiring fault. GM Car A/C Service diagnoses AC electrical faults systematically — our technicians use multimeters and circuit testers to find the exact failed component.
Can a weak battery cause car AC problems?
Yes. A weak or failing battery causes voltage drop that affects AC compressor engagement, blower motor speed, and control module function. In Chennai's heat, batteries degrade faster than in cooler climates. If your AC shows intermittent or irregular behaviour, a battery health test is part of our diagnostic process.
How long does auto electrical diagnosis take?
A focused auto electrical diagnosis at GM Car A/C Service typically takes 30–90 minutes, depending on fault complexity. Simple relay or fuse repairs are short jobs. Complex wiring fault tracing may take longer. We provide a clear timeline and estimate before any repair work begins.
Do you repair rat bite / rodent damage to car wiring in Chennai?
Yes. Rat and rodent bites on wiring are a very common cause of sudden car electrical faults in Chennai — AC cutting out, warning lights, dead sensors, or a circuit that stops working overnight. GM Car A/C Service traces the chewed wiring harness, repairs or replaces the damaged section, restores proper insulation and connectors, and tests the circuit end to end. We fix the actual bitten wiring, not just clear the fault code.
What tools do you use to diagnose electrical faults?
GM Car A/C Service uses multimeters, clamp meters for current-draw testing, circuit testers and, where relevant, an OBD scanner to check stored fault codes. Wiring diagrams for the specific make and model are used to trace circuits accurately rather than guessing at components.
Can electrical faults come back after repair?
A properly diagnosed and repaired electrical fault should not recur from the same cause. If a similar symptom returns, it is usually a different component in the same circuit — bring the vehicle back so the circuit can be re-tested rather than assuming the earlier repair failed.
Do you service electric vehicles (EVs)?
We service the AC and general electrical systems of electric and hybrid vehicles — cabin cooling, wiring and diagnostics. High-voltage battery and drivetrain work needs the vehicle manufacturer's own service network. Call +91 8428000085 to confirm we can help with your EV model.
Related pages and areas
Tell us what the car is doing
We will call you back to confirm a slot. Nothing is charged and nothing is booked until we have spoken.
- +91 84280 00085Customer Service · Individual car owners
- Message us on WhatsAppMon–Sat 10:00 AM – 8:00 PM. Sunday closed.
