Driver's Seat Electrical Repair

So two adjustments had never worked, rear height up and lumbar down and one adjustment had worked intermittently which was backrest recline. All the archives say the seat switches are the culprit but luck was not on my side .....

To trouble shoot I ended up hooking the seat up to the electrical connector in the car with the seat loose and probing around with a multi-meter.

After a number of false turns the relay pack was at fault, you could hear the relay click when the switch was pressed but no motor action and no voltage at the motor.

OK so remove relay pack (much grief) and clean the connections, put all back together and same symptoms, crap.

Removed the relay body and hooked the seat back up so I could see the relays and now get a meter to the various connections, seems the relays operate in pairs but their was a common relay which activated the three adjustments which didn't work. Getting close now ...

So I get a tooth pick and push the contact on the relay closed, all three adjustments work, voila or Yeeehahhh or whatever!!! Turns out the little copper braid which connects the relay arm to the body was impeding the arm movement. A little adjustment and we are in business.

To have all 12 way adjustment, luxury  !!!!!

	So before I realised how dumb I was and I could Ohm out the switch's before I dismantled and found nothing wrong here is the inside of a switch .......
	Underside of the seat and the black box where all the seat controls interface.
	Here is the cheat sheet to tell you where all the connectors (there are 15) go.
	Here is the PCB which is bowed because someone hadn't assembled the metal support under the seat  properly putting unnecessary pressure on the PCB. Several joints needed to be resoldered..
	Offending relay box is on the left.
	Relay box pried out from its home, note the 928 number, guess you can order one for $$$$$$$
	Only way to get the relay housing off is unsolder all the connections, this is the housing with relay PCB removed.
	Relays !!!! Spent time cleaning the contacts with emery paper.
	Here is the offending Relay, arrow points to where the braided cable was impeding the relay movement, by this time I was so overjoyed at finding the problem I couldn't focus the bloody camera !!!!!

Back