EV and hybrid code
P0A93: Inverter cooling system problem
How this range is built
| Part of the job | Low | High |
|---|---|---|
| Parts | $50 | $600 |
| Labor: 1 to 3.5 hours × $125 to $175 an hour | $125 | $613 |
| Fees: shop supplies, disposal, diagnostics | $20 | $80 |
| Total, rounded | $190 | $1,300 |
The hourly rate is the BLS Occupational Employment and Wage Statistics, May 2025 average pay for this trade in Boston, $31.54 an hour, times 4 to 5.5 to cover what a shop bills (overhead, tools, insurance, profit). Parts are a band from budget aftermarket to the manufacturer part. Full method.
Not a repair shop, estimates only. Typical range, estimate. Not a quote. Your car, parts and shop change the number.
This is the range for the most common fix, ev battery coolant service / pump. Which repair your car needs depends on a proper diagnosis.
The cooling system for the hybrid inverter is not working as well as it should. This is common on Toyota hybrids, but it can vary by make, so check the scan tool or manual. The inverter can overheat and limit power, which is the car protecting itself.
- Safe to drive?
- Short trips only
- Most common cause
- Failed inverter coolant pump
Drive gently and only for short trips. Stop if the car limits power, shows a red warning, or runs hot. Stop driving if the car goes into limp mode, shows a red warning, loses power, or you smell something burning. Call a tow rather than keep driving.
What you may notice
- Hybrid warning light on
- Reduced power
- Warm or hot smell
- Coolant level low
Common causes, most likely first
- Failed inverter coolant pump
- Low or old inverter coolant
- Air in the cooling loop
- Blocked hose or radiator
- Failing inverter
Check this first
Check the inverter coolant reservoir level, which is separate from the engine coolant on many hybrids. Do not open hot systems.
Other repairs that sometimes fix P0A93
| Repair | Typical range, Boston |
|---|---|
| Hybrid inverter / converter repair | $1,050 to $4,475 |
| Coolant flush and refill | $120 to $370 |
| Diagnostic scan (check engine light) | $60 to $290 |
Before you pay
- Ask the shop what test showed this part is the cause, not just that the code appeared.
- Ask for parts and labor listed separately, and for the hours.
- Ask for a written OK before any extra work. Massachusetts rules require written authorization before repairs.
Got a quote already? Check it against the range. Want to see if your car has a recall tied to this problem? Check recalls by VIN.
Need to read a code yourself? OBD-II scanners on eBay (affiliate link, disclosure).
P0A93 questions
Is it the engine coolant?
Often it is a separate loop on hybrids. The inverter has its own coolant, reservoir and pump, apart from the engine coolant, so check the right tank and use only the type your manual calls for.
What happens if it overheats?
The inverter can limit power or shut down to protect itself. You may notice the car gets weaker or refuses to go into ready mode, especially after hard driving or in hot weather.
Do I need a new inverter?
Usually not at first. The pump and coolant are more common, and they cost far less. A shop should test the pump and check for air in the loop before anyone talks about an inverter.
How much does it cost to fix P0A93?
The most common fix, ev battery coolant service / pump, has a typical range of $190 to $1,300 in Boston. It is an estimate built from parts prices and local labor wages, not a quote. Your car and shop change it.
Related codes
- P0A94: DC/DC converter performance problem
- P0A78: Drive motor inverter performance problem
- P0A80: Hybrid battery weak or worn out
More ev and hybrid codes
Code meaning written in our own words. Some codes mean different things on different makes, so check your scan tool or manual. Not a repair shop, estimates only.