View Full Version : Trouble code PO505

23rd January 2007, 02:39
This weekend I had completed a tight turn around in a parking lot and was getting ready to head back down the road, when the check engine light came on and the engine stumbled. I blipped the throttle a few times and the enging smoothed out somewhat. It took @ a 1/4 mile to start running smoothly again.

The speedo was dead and the odometer wasn't moving. After a mile or so, the speedo started to work again.

I headed for the dealer and dropped it off to have it checked and the voltage regulator recall done.

The trouble code was PO050-"loss of idle air control" They cleared the codes and couldn't get it to duplicate :doh . It was already running fine by the time I took it in. They can't tell me what caused it or if I can expect it to happen again.

Anybody had similar or know anything more about this?

Also they didn't have the bolt/bracket necessary to do the recall. Make sure they have them in stock before you drop your scoot off.

Thanks in advance.

Screw Loose Dan
23rd January 2007, 12:57
Summarized from 07 Sporty Electrical Diagnostic Manual:

P0505 - Loss of idle speed control

Loss of idle speed control will result if the idle RPM is +-200 from present idle speed and IAC motor is at zero or maximum for greater than 5 seconds.

- Loss of idle speed control doesn't necessarily mean that the IAC is bad. There are other causes such as intake leaks, misfiring cylinder.

- Leaking injectors can cause poor idle. To check for leaky injectors remove A/C. Then with throttle wide open, turn key to ON for 2 seconds and then off for 2 seconds five consecutive times. Replace injectors if there is any evidence of raw fuel in the bores.

- Vacuum leaks - check for leaks

- Contaminated fuel

- Excessive Oil in crankcase

- TP sensor reading greater than 1 % (cable misadjusted), battery less then 9 Volts, or vehicle speed sensor (VSS) greater than 0 will disable idle speed control.

- Loss of battery power to terminal 31 of ECM.

Since your bike is running fine now, I won't go into all the diagnostic steps. But maybe that gives some insight to what might have been a problem.

I haven't had this error code. But maybe a bit of bad gas caused the problem?

23rd January 2007, 13:46
- TP sensor reading greater than 1 % (cable misadjusted), battery less then 9 Volts, or vehicle speed sensor (VSS) greater than 0 will disable idle speed control

Dox, you mentioned "a tight Turn in a parking lot". If you had the handlebars at full lock and the cables/wires around the steering stem are too tight this might be pulling on them.

We had a guy in the shop once whose bike would only start if you had your right foot on the floor(while on the bike). Left foot down; no start. We could duplicate this repeatedly and it was creepy. While watch in him demonstrate we noticed he moved the handlebars slightly, on inspection we found a wire broken inside its' insulation. The movement of the bars was just enough to create an opening in the starter motor switch circuit.

At idle , turn your bars, if the rpm increases at full lock then there is not enough free play in the cable adjustment. Try the same with the engine off but ignition on and see if your speedo or tach go out again. Check for tension or pulling of the wiring loom coming from these.

I hope this helps. Clayton

24th January 2007, 04:30
Thanks guys,

I'll check the obvious 1st.

24th January 2007, 13:14
Speedometer Signal and Code P0505
The speedometer signal is an extremely important input for the Delphi fuel
injection system. The ECM monitors throttle position and speed signal inputs in
order to properly maintain the set idle speed. If the ECM loses the speed signal
for any reason while the throttle is closed, the ECM assumes the vehicle is
stopped and will adjust the idle air control counts to bring engine rpm to the set
idle speed. This could set a P0505 code and adversely affect engine idle.

28th January 2007, 13:13
make shure your battery termnals are tight, could be a little loose dropping voltage.