Missing Power light.

thissoan · #1 02-20-2010, 06:45 PM

I'm guessing this subject has had a thread previously.

Rebuilt the transmission on my '93 SVX 4EAT aussie delivery. I think this particular SVX is on its 3rd transmission.

Have arranged for the instalation of an upgraded higher performance Nomad Valvebody kit running higher line pressures and clamping forces in tranny replacement with an additional external tranny cooler.

Since I took delivery with nomad tranny I have noticed that the power light still comes on as per diagnostic when turning on ignition but when driving the SVX if I floor the gas pedal and kickdown the power light no longer comes on at all.

My concerns are that the transmission's TCU map-shifting is screwed up due to no connection or something of a simular nature involving the new valve body.

Can somebody shed some light on why no power light on kickdown and does that mean decreased performance from motor or transmission or both.

thissoan

b3lha · #2 02-21-2010, 05:41 PM

The TCU decides to engage power mode based on the signal from the throttle position sensor.

The first thing to do is check for TCU error codes. If the TPS is faulty, it can trigger an error code. Alternatively, if something some other part is considered faulty then the TCU might be in a kind of safe mode. You didn't mention anything about the power light flashing 16 times, but it's probably worth checking anyway just to be sure.

The next thing to do is to test and adjust your TPS. If the calibration is off then it will affect not just the power mode engagement, but the shifting as well.

thissoan · #3 02-21-2010, 11:29 PM

Thanks for you remarks. The SVX is still in a workshop getting rear sub frame bushes repaired. When I last drove with this problem the power light did not flash any error codes. Does it store them? How can I access ECU memory? I had some success with my ’92 legacy checking and clearing codes I guess the methods are the same.

oab_au · #4 02-22-2010, 01:44 AM

Quote:

Originally Posted by thissoan

Thanks for you remarks. The SVX is still in a workshop getting rear sub frame bushes repaired. When I last drove with this problem the power light did not flash any error codes. Does it store them? How can I access ECU memory? I had some success with my ’92 legacy checking and clearing codes I guess the methods are the same.

Hi Mate, you need the TCU codes. This in the How-tos, here.
http://www.subaru-svx.net/photos/files/How-To/25335.doc

Cheers Harvey.