Johnnyas

Hey guys, so I've been having trouble where 1st and often 2nd gear won't engage when pulling away. ECM fault code pointed to shift solenoid A not working properly.

Pulled sump off today and pulled out all the solenoids, cleaning them and testing.

All of then apart from S1 read around 14ohms, however S1 is reading only about 2ohms!

If you give it 12v over the terminals the plunger inside works properly though.

I'm no electrical expert, but I'm assuming that even though it works the ECM requires around 14ohms resistance for the solenoid to work? And less than this causes the ECM to throw up code and ignore S1?

I don't want to buy a new S1 if possible as I know how expensive they are!!

rkw77080

According to the repair manual, if you can confirm that the solenoid plunger moves, you're OK.

Johnnyas

Yeah moves and operates fine when fed power, however the manual does specify resistance there.

The other three solenoids function the same however are generating 14ohms each.

Either way I put it back in to see if anything has changed and sadly it hasn't, still pulling away in 3rd and showing error code for S1
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Gronemus

What are you using to power the solenoid when you are checking it? If you are truly measuring 2 ohms for the coil resistance you have a shorted coil inside that solenoid which is going to require roughly 7 amps of current to actuate instead of the normal 1 amp (assuming about 14 volts being supplied by the system). If you are testing it by connecting it up to a battery then its no surprise that you can get it to work. However, I suspect that the driver circuitry in the controller is unable to supply that much juice to the solenoid and it isn't moving because of that.

I'd replace the solenoid...

Johnnyas

I suspected the answer was something like that, thank you. I've tried looking for a second hand solenoid but I'm chatting to someone about buying a whole transmission for spares.

But yes was simply powering on a 12v battery with a 10w bulb in series.

bradland

Rockauto sells S1 and ships internationally- https://www.rockauto.com/en/catalog/...+solenoid,8476

Johnnyas

That's for the 6-speed, they only list s3 for the 5-speed