Justanumpty

[Justanumpty]

Hi , I have made a major schoolboy error, after fitting a new EGR, I decided to replace the battery too. I did not see that the polarity on the new battery was reversed. I took it for granted that it was same as old one. (shame) When I connected the Earth / Ground black connector to what I thought was Negative, it started sparking and wiring started smoking at loom above starter motor, where 2/3 wires all branch together. I quickly realised something bad was happening so quickly disconnected the battery, and re-fitted the older battery. The central locking is not working, radio, heater fan not working, heated seats not working, rear wash/wipe, N/S 12v outlet not working but O/S is working. Lights/horn/indicators/dials(after dial dance) all working. Had a look at a few fuses and they "look" okay. Swapped rear blower relay with accessories relay, but still same. Can anyone suggest which relay or fuses to check for basically all the central dash switches ?? If I can find a relay or fuse to change, then that would save me having to investigate the wiring loom until last. 2007 stow n go grand voyager. Gutted and angry at myself. Basics. Thanks, fingers crossed P.S. car started fine and runs, and after clearing code P0402,no more engine light. 

[RichardM]

Sorry but would suggest ECU has been electrocuted! - There is a feed to this that does not go via the ign switch i.e. live all the time. 

[bignev]

Sadly, Richard is probably right.

But, give it a go - disconnect the battery for half an hour,  as a few of those circuits will reset this way. I would say pull the IOD fuse, but in this case go the whole hog.

There are also the fuses under the steering wheel as well as the box under the bonnet, just check them all and hope something has done its job and protected things!

[Justanumpty]

Thanks Richard/Big Nev, All I can hope for, is replacing a lot of the relays and fuses (thanks for the heads up about more under steering column),then if that fails, investigate the wiring loom above the starter motor, as that is where a lot of smoke and even bubbling was happening. I will have to unwind the loom tape, and inspect each wire individually, especially the ones next to the starter feed (is that the yellow, as I believe?) not easy to access deep behind the radiator, but worth doing to save the baby bus. Thanks guys.

[Justanumpty]

Forgot to say, fitted a brand new alternator and 2 x drive belts, same time as fitting EGR, and while O/S wheel arch inner panel off, changed the oil and filter too. Just hope I didn't fry the new alternator too. The engine started and ran with no dash warning lights, no engine light or battery light, but when I turned ignition off, engine stopped as should, but ignition lights stayed on for a while. I eventually got them to go off, by turning key on/off a few times. Does this imply a damaged starter solenoid ? Should a replacement be added to the list of relays and fuses, as a belt and braces approach ? Appreciate you help guys. I am still ashamed and gutted for doing this, as have worked on my own cars all my life, so can't believe I was so stupid. Lesson for others, take nothing for granted, even if the items look identical (Exide 72Ah battery looked identical, but polarity was reversed). Head hung in shame.

[Justanumpty]

Wee update, disconnected battery as advised, and same results as before disconnection. Had an even closer look at every fuse. IOD was in fact blown, so changed that, then got radio back and engine running, but new warning traction control off ! Then noticed one green tower fuse (19) BCM was indeed blown too. No spare so swapped with Tailgate one. Engine started and ran with no warning lights now. Radio and heater fan controls now all working, just the hazard warning switch and heated seats not working, so investigations ongoing. There is one green tower fuse that says HZD/?? Read somewhere, to change that too, even if it does not look blown, so that will be my next step. Think I might have just dodged the car crusher bullet. Fingers crossed. 

[Justanumpty]

Central locking back working too !