Stupid mistakes you thought you'd never make

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Stupid mistakes you thought you'd never make

Post by DarrylWebb » Thu Jan 25, 2018 5:41 pm

"How could anyone be so stupid as to connect a car battery the wrong way around?"
Well, I had to wait until I was 49, but I did it for the first time last month.

During the winter I've been applying much TLC to my stepson's neglected 2005 Hyundai Coupe. Said car is 'maintained' by somebody else, but I drained 3 litres of treacle, the air filter was black, the oil filter was rusty and I've seen better brake discs in the breaker's yard. Over several weekends I tended to these, and refurbished the scruffy alloys. I even started warming to the car for putting up with the poor care it's had in the past.

It's been sitting at our house for a few months. All repairs complete, I re-charged the battery and fitted it. As soon as I attached the cables to the poles the horn sounded. With too many other things running around my head, I ignored Hyundai's subtle warning as the huffy alarm of a 12 year-old Korean shed. So I disconnected the horn.

Turn the key, the starter kicked and died, but the way it did it didn't sound normal at all.

"You idiot". I discovered my own mistake. I re-connected it properly but turning the key had the starter turning the engine but with no impression of anything firing. I feared this could be expensive, more costly than the car's value.

A major 120A fuse in the engine compartment had blown. None in the local motor factors. I could only get one off eBay, but at least the next weekend the car was running.
However, heater, A/C stereo, clock were still not working. Reversed polarity had blown a couple of fuses in the fusebox below the dashboard.
I replaced those, getting the clock and stereo working, but the heater fuse would blow as soon as the key was turned to 'ignition'. I don't think stepson will live without a heater these next couple of months,
S'pose I'd better get a Haynes manual to trace the wiring to give me a clue. Haynes don't do a manual for the Hyundai Coupe.
I lucked into wiring diagrams on a Coupe forum, but as electrics are not my forte, it didnt give me an "AHAH!" moment. With the addition of some Googling, my best starting point was the heater relay. Next problem, it's an odd relay, only used in Hyundai/Kia for the heater blower motor and diesel glow-plug heater circuits. I took a punt on eBay and found one cheap at £10.

A stroke of luck, that sorted the problem. £20 of fuses and relays later, but several hours out in the January cold, it's back as it was before I made a daft error.

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Stupid mistakes you thought you'd never make

Post by peter freeman » Thu Jan 25, 2018 6:00 pm

My workmates BMW had a black lead on its battery +ve - don't know if they still use black for +ve. He tried to jump start his wife's Nissan - blew the top off her battery - fortunately he was not leaning over it when he connected the jump leads.

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