Hey Guys,

I have a Toyota SAI 2010 which is used for tourism and I am based in Sri Lanka.

the vehicle gives the P0A94 Error - DC/DC converter performance error.

the error only occurs when driving on the free way clocking at 100KMPH and around 15-20Mins Drive.

I have changed the Inverter, DC to DC Converter, 12V Battery and still the issue is not sorted out. Does anyone out here have got the same issue and got it rectified. I am desperately in need of a help.

Thanks for your help.

Chamath

 

There are literally a dozen different versions of P0A94. What was the detail code?

Here are the potential causes of all P0A94 variants according to the Toyota manual:Battery smart unit
Cooling fan system
Engine assembly
Frame wire
Fuel level
Hybrid battery junction block assembly
Hybrid vehicle control ECU
Hybrid vehicle transaxle assembly
IGCT No. 3 fuse
Inverter cooling system
Inverter with converter assembly
Service plug grip
Water pump with motor assembly
Wire harness or connector

 

Hi,

Thanks for your reply. We checked all the below and no issues were found.

does this has anything to do with the Gear Box? Transmission?

 

Are you claiming that you checked all of the items I listed? I find that impossible as there are detailed diagnostics for each of the 12 or so detail codes. Furthermore, you're asking about the transaxle when I clearly indicate...

Again, what was the detail code?

 

Hey,

It’s like this. Since the vehicle is in Sri Lanka, over here mechanics are being unable to trace the exact issue of the vehicle.

what I have done with the mechanic is as below.

hybrid battery pack replacement
normal 12v battery replacement
Inverter Replacement
DC to DC Converter Replacement

I have attached herewith some images of the issue.

P0A94-127 is the detail code.

Thanks,
Chamath S.

 

-127 is Boost converter overvoltage signal detection (overvoltage due to system malfunction)

Likely faults:

• HV relay assembly
• Inverter with converter assembly
• Service plug grip
• Frame wire
• Wire harness or connector
• Hybrid vehicle transaxle assembly

If ANY of the following codes are present, they should be pursued first:

P0A1A (all INF codes) *1 Generator Control Module
P0A1B (all INF codes) *1 Drive Motor "A" Control Module
P0A1D (Except INF code 390) Hybrid Powertrain Control Module
P0A3F-243 Drive Motor "A" Position Sensor Circuit
P0A40-500 Drive Motor "A" Position Sensor Circuit Range / Performance
P0A41-245 Drive Motor "A" Position Sensor Circuit Low
P0A4B-253 Generator Position Sensor Circuit
P0A4C-513 Generator Position Sensor Circuit Range / Performance
P0A4D-255 Generator Position Sensor Circuit Low
P0A60 (all INF codes) *1 Drive Motor "A" Phase V Current
P0A63 (all INF codes) *1 Drive Motor "A" Phase W Current
P0A72 (all INF codes) *1 Generator Phase V Current
P0A75 (all INF codes) *1 Generator Phase W Current
P0A78-113, 128, 266, 267, 279, 284, 286, 287, 306, 503, 504, 505, 506, 523, 586, 806, 807, 808 Drive Motor "A" Inverter Performance
P0A7A-122, 130, 322, 324, 325, 344, 517, 518, 809, 810, 811 Generator Inverter Performance
P0A90-509 Drive Motor "A" Performance
P0A92-521 Hybrid Generator Performance
P0A94-172, 442, 547, 548, 549, 553, 554, 555, 556, 557, 585, 587, 589, 590 DC/DC Converter Performance
P0AA6-562 Hybrid Battery Voltage System Isolation Fault
P0ADB-227 Hybrid Battery Positive Contactor Control Circuit Low
P0ADC-226 Hybrid Battery Positive Contactor Control Circuit High
P0ADF-229 Hybrid Battery Negative Contactor Control Circuit Low
P0AE0-228 Hybrid Battery Negative Contactor Control Circuit High
P3004-803 High Voltage Power Resource

If none of the above are present, there are 23 steps to diagnosing P0A94-127 resulting in replacement or repair of the listed faults.