Fact - stranger than fiction...

Jim Warman · May 22, 2009

An acquaintance has the contractfor our towns ambulance service.. given that this is a "difficult" customer (unrealistic expectations as to "ready" times, unrealistic demands as to 'line jumping' and 24/7 service, and unrealistic demands as to deep discounts for Cadillac service), I would personally prefer that this man keeps this contract and spare us the pain.

He has an 03 7.3 that has a recurring P1729 - 4X4 low switch failure... WSM sends you to PC/ED... PC/ED sends you to WSM.... This is if you access the F350 manuals. However, this is a 2WD E350.... Yes, the OCS light starts flashing and yes, the shift scheduling is affected.

Anyone seen anything this goofy before I hit up hotline?

Keith Browning · May 22, 2009

That certainly is an odd one Jim and sorry to say I have never run into something this goofy. Do you think the Hot-Line will tell you to replace the 4X4 switch?

Mekanik · May 22, 2009

Hotline Response- Jim, check your connection at the 4X4 switch. We have had concerns of this.

Is it possible that they have been swapping PCMs and this truck has a PCM from a 4X4 vehicle?

Mekanik · May 22, 2009

I'm curious, when you hook up IDS, does it recognize that it is an E350 and not a F350?

Jim Warman · May 23, 2009

I haven't seen this bus.... the tech has either a Solus or a Genysis (suffering from CRS) that works well on anything else it get's hooked up to (6.0s and 7.3s included). Neither of these will identify a vehicle without operator input....

It would make it easier if I could hook the IDS to it - but, at this time, nobody is willing to spend the money...

Dr_Siko · May 23, 2009

There is a takeout in the harness and the wires are terminated with heat shrink, there is a 4x4 input and there are Clean tach and vss outputs also there maybe a chaffed harness or water intrusion at the PCM connector allowing voltage into this circuit. Is the code in set because it is seeing a low range 4X4 input and too high VSS? I will try to look into the wiring diagrams to verify my theory. When they convert one of these to 4X4 ie Quigley this is used to modify shift timing and limit engine rpm low range. Good luck Jim, I know you will figure it out. Is there a PID for 4X4?

Dr_Siko · May 23, 2009

Jim, the take out is going to be beetween the brake master cylinder and the air cleaner taped to the large convoluted harness very close to the air cleaner mounting bolt. The wires will be labeled CTO, 4X4, VSO, TPO.