P0706 - Transmission Range Sensor.... Again....

[margo88]

2004 A4 B6 Quattro Tiptronic with 90k miles. I had the clunk when putting it into reverse with limp mode and the P0706 code. I replaced the transmission range sensor and everything has been great for 2-3 weeks. But this morning, it started doing the same thing again. Just ran a scan and the P0706 code has returned. Is it likely the transmission range sensor I bought is also bad? Or is it a wiring issues somewhere? Any ideas/hints where to start tracing some of that down? It will be next weekend before I can start tearing it apart, but if I need to buy parts, I'd like to get them ahead of time.

Newest Scan:

Address 02: Auto Trans Labels: 01V-927-156.lbl
Part No: 8E0 927 156 P
Component: AG5 01V 1.8l5VT USA 1213
Coding: 0001002

1 Fault Found:
17090 - Transmission Range Sensor (F125)
P0706 - 003 - Implausible Signal - MIL ON


The switch I purchased:
https://www.amazon.com/dp/B07V3272BP

[Gin+]

My $ would be on the range sensor being defective but YMMV. I vaguely remember a post somewhere where someone drilled out the rivets, cleaned up the contacts and put it back on the car.

[margo88]

On the second, newly purchased one being defective as well? The new one was only $36, so I'm wondering if it's cheap and failed, but also looking for if someone knows how to test the range sensor off the car so I can find out if it's wiring or if he new range sensor is also bad.

[Puddin Tane]

The new one was only $36, so I'm wondering if it's cheap and failed...

Most likely, yeah. That price is for a second quality clone switch, a false bargain. You need to splurge and get the real deal, but don't buy the Genuine Audi part. That's just a re-branded Intermotor NS-349 neutral safety switch with a whopping mark-up. The latter is what you go hunting for.

That post Gin+ mentioned.

As for the wiring being bad, the most likely failure point is water infiltration and corrosion inside the switch's D-connector-- easy to check for and mitigate. As for testing the wiring more extensively I suggest referencing that schematic in the Bentley manual to find out where the wires go then testing each one for continuity, but I think your time will be better spent swapping in an Intermotor switch.

[Puddin Tane]

Rock Auto has it. They're also hard to beat for price and have a great rep.

[EuroxS4]

When it comes to parts, I only use audi original or oem. That cheap switch is just straight china garbage. That being said could it have failed, yes possible, but it would be good to check the wiring for the switch inside the rubber boot at the connector. With the age of these cars and the location of that wiring I wouldn't be surprised if the insulation was coming off the wires from all the heat cycles.