Originally Posted by hilde3
Car is a 2006 suzuki forenza. My engine light comes on at times and gives codes P0703, P0705, P1779. Anybody else have this problem? What was the outcome?
Similarly, I'm addressing an intermittent problem on a 2006 Reno for a nearby shop. The transmission seems to "Bump" intermittently while cruising and will set a P1779 in the TCM & a P0107 in the PCM when that occurs. It doesn't feel like an engine misfire. When it happens, the MIL is illuminated and the transmission shifts are harsh until the DTC is cleared.
It also sets a P0703 every time the key is cycled, which disappears as soon as the brake pedal is depressed (thinking it's a default test of the brake switch circuit). A new brake switch did not affect this.
Vehicle has a new TCM & PCM (from the dealer) but all symptoms are the same with the new modules. The VIN's been written to PCM and all initializations have been done to both modules using a Tech 2.
While performing the troubleshooting chart for P1779 I can sweep the TPS from 0% to 100% while watching TCM data but when watching PCM data it only sweeps between 18.4% to 25%. Both of the "old" modules displayed similar data.
All voltage drop tests show less than .050 but the problem is intermittent so I've asked the shop owner to record the voltage readings on the TCM grounds, ignition & battery feeds at the time the problem occurs (which he said he will do later today). I'm guessing there may be a drop occurring at times.
Any help will be greatly appreciated.