Technical Electrical problem?

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Technical Electrical problem?


New member
Sep 25, 2021
Got a 53-plate Punto 188 1.2 8v we use for running about town and touch wood for the missus to actually learn to drive. We've only had her 8 months but have had a few issues with her.

She's always seemed to run a wee bit rich and can be rather lumpy at times.

Power steering light was intermittently coming on but touch wood hasn't done so for a while.

Then we got a few ECU P0606 codes thrown up.

And now we have had an engine coolant sensor P0115 code chucked at us.

This morning when I looked at the voltages at the battery terminals it reads 12.56 volts, it goes up to 14.09 volts at idle, 13.86 volts with the blowers on full, the heated rear windscreen on, and headlights on dipped beam. This drops to 13.81 volts with full beam on. The voltage on the ECU sits at about 13.8 volts on idle and drops to 12.9 volts with the blowers on full, heated rear windscreen on, and headlights on dipped beam. This further dropped down as low as 12.6 volts with full beam on. Screenshot attached.

Do the voltages seem too low? Battery needing replaced? Alternator weak?


Those are good voltages apart from the ECU voltage going lower. The ECU voltage going lower when you operate more devices could be caused by the returns for the heater, lights, etc going to the same Earth block under the battery. That earth block is connected to the gearbox earth half way along the length of the wire. The bolt holding the earth block to the chassis and gearbox earth might need cleaning up.