I finally retired by 99 V70 GLT and picked up a gently used 08 XC70 with only 90,000km for my commuter car. I am having intermittent problems with the push button start.

When inserting the key, more often than not, I get a no start. No accessories and no starter. I can flip the key over and sometimes that works. getting worse now and cant rely on going anywhere with the car. Doesn't matter which key I use.

Cleaned the battery terminals (as suggested in another search) and replaced the key battery. Brake switch seems to be working fine. I now get a clicking sound in the shifter whenever I use the brake - only while in park with engine running.

So I think there is something in the shifter switch or maybe column lock intermittently preventing a start?

anyone experience this or have any suggestions?

Update - Indy replaced the ignition switch (transponder) and everything working fine. About $500CDN including a hour labour.

I did have a work around while waiting for repair. When the car would not start (most times), I sprayed electronic cleaner in the ignition slot and this would work every time to start the car.

I have this seemingly exact problem. For about a yr, insterting thr key fob and pressing it in a bit while pushing the start button would work, now nothing.
Do you know exactly what was replaced? Part number?

Thanks

To replace the module requires a software update, which means a visit to the dealer and the price of repair just got high.

To remove the module, watch this video for 10 minutes:

https://www.youtube.com/watch?v=vTIqmZ163nw

Then take the module apart and clean it:

https://www.matthewsvolvosite.com/forums/viewtopic.php?t=81397

Just make sure it is completely dry before reassembling it and putting it back in the car.

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Keeping it running is better than buying new

Removed cleaned and lubed the start module, no change. I remembered, the last time I drove the car I ran over a branch in the road, I heard it hit the floor of the car. The skid plate was removed when I flushed the Transmission. I hadn't put it back on yet. That was dumb. Is there something under there that might cause this condition. I'm going to look under today but will only be able to diagnose the obvious.

Yup, it's obvious. Braided wire between the solenoid and the starter corroded and separated. Air gap. Live and learn.

I wonder if I fashion and could solder a replacement.

The wire is copper and can be replaced. Easier if done on a work bench. If you do manage a replacement, it should last for a few years.

A starter replacement is not too bad:

https://www.fcpeuro.com/products/volvo-starter-motor-s60-s80-v70-xc70-36000041

Search the web for better prices? and free shipping?
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Keeping it running is better than buying new

Excellent idea. I saw that video, seems straightforward. I will attempt the cleaning first.

Thanks.

You may need a new key slot, but verify that the battery is at least at 12V. The 'click' when pressing the brake in park is normal, that is the disengagement of the P lock allowing you to shift from P to N.

Your key is supposed to be drawn into the slot and locked in until the engine is turned off. Previous owner may have forced the key out of the slot.
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Keeping it running is better than buying new

Would new key slot require any programing to be compatible with the old key? also is "new Key Slot" the same as
"replaced the ignition switch (transponder)"?

Found this on Tasca. Ignition Switch - Volvo (31268326) Right direction?

Checked the battery and a bit under 12V. Put the tender on it and got it over 13. started after about a dozen tries using both fobs. shut the car off, and no restart.

Got an appointment at Volvo indy on Thursday see if they can figure out. Another at dealer the following Monday if they cant. Hopefully it starts so I can get to the shop. Will report back findings.

Upon further review -

Do you have an aftermarket remote starter? Or anything else electrical?

No - everything stock as far as I know.

I have no input as to your problem but -

If it turns out that you have to replace the key slot, I own an '08 and a '12 XC70.

The key slot is different in the '12 - there is no mechanism that pulls the key in, or pushes it out - the key slot just has a gentle detent that holds key in place.

See if your car can be fitted with a '12 key slot.