The customer came to us with the well-known DTC (diagnostic trouble code) P0A80 “Replace Hybrid Battery Pack” after an initial check at the local Lexus dealer. The conclusion from them was that the customer needed to change their entire HV battery for a total cost of about EUR 4,000.

Surely there had to be a happy medium between driving with a faulty battery and spending that amount of money on a brand-new pack. We connected our diagnostic tool and could quickly see that the fault was indeed caused by a single module, or in fact a single cell within that particular module that was 1.4 volts lower than the rest of the cells. This most likely meant we had to get a replacement module with similar “wear” as the rest of the modules, obviously without being broken but a new one would not work well with the rest of the pack. Following a search, we managed to source a used module in good condition and we then removed the battery from the vehicle.

With the battery out and the protective covers off, it was easy to measure the faulty cell with a normal voltmeter to confirm what we saw in the diagnostic software. The cell was in the middle of the pack, which meant tearing the whole thing to pieces. When we performed this procedure, it was also apparent that the copper bars connecting the cells were severely corroded, so we took the opportunity to give them a thorough clean as well.

Now with the replacement module in place and the busbars cleaned, we reassembled the pack and put it back in the vehicle. On first start-up, the DTC was gone and the cell delta (difference between lowest and highest cell voltage) was below 0.10 volts. The customer was very satisfied as the vehicle went back to performing like a proper hybrid vehicle once more. In this case, the customer “saved” approximately EUR 3,000, which in itself has got to be a success story.

Manufacturer: Lexus

Model: GS450H

Electric motor: AC synchronous, permanent magnet

Motor controller: n.a.

Power: 144 kW (197 hp)

Torque: 275 Nm

Batteries: 7.2 VDC Ni-MH (nickel metal hydride) modules

Voltage: 336 VDC fully charged (288 VDC nominal)

Capacity: 1.9 kWh

Range: n.a.

Charger: n.a.

Cost: contact us for a quote