c4 2.0 HDI 2005 wont start after change radio

[VeigaN]

Good afternoon. Here I am again…


My 2005 C4 2.0 HDi had an aftermarket 2-DIN radio. The previous owner gave me the car's original radio, along with the screen and all the accessories.
Today I went to swap the radio and now the car won't start, and there is no information showing on the odometer or the tachometer. The hazard lights were also on, and I had to disconnect the battery.
What could have happened?
The only thing I did was, literally, unplug and plug in connectors… I'm getting desperate with this car.

[Paul-R]

Did you disconnect the battery before starting the job? You could try a BSI reset.

viewtopic.php?p=601679#p601679

[windy1603]

Check fuses in BSI as radio feed also feeds comm2000/immobiliser pickup. If OEM radio works was a adaptor lead fitted for the Aftermarket radio or did they swap around cables they may have grounded the CAN lines and on a aftemarket radio the CAN ISO pins have another use.

If not check radio harness from head unit as there are a couple of splices in the cable and connectors that may have got partly disconnected

[VeigaN]

Did you disconnect the battery before starting the job? You could try a BSI reset.

viewtopic.php?p=601679#p601679

No, i didn't. I left the car all night with disconected battery and by morning it starts like a charm.