Click/tapping felt in 2006 xc70 automatic gear shifter when key turned to position 2

greentrout · Post by **greentrout** » 25 Dec 2020, 23:49

Had lots of intermittent issues with electrics/canbus. My car's now stuck in limp mode and mostly only starting with battery pack. But when it's going wrong one consistent symptom has been a mechanical tapping felt through the automatic gear lever/shifter when I try to start up. The clicking/tapping happens during setup key in position 2 as the car runs through it's diagnostic sequence.

Has anyone had this experience? Is it linked to the canbus/electrical issues or a seperate switch/connector issue physically linked to the shifter. The lever physically taps suggesting a servo driven repeating failed attempt to do something. Then diagnostic lights go on, and I'm stuck in 3rd gear limp mode.

Any suggestions? Havent removed unit covers yet, but that's my next move, alongside checking major electrical connections.

Post by **firstv70volvo** » 26 Dec 2020, 13:31

greentrout wrote: ↑25 Dec 2020, 23:49 Had lots of intermittent issues with electrics/canbus. My car's now stuck in limp mode and mostly only starting with battery pack. But when it's going wrong one consistent symptom has been a mechanical tapping felt through the automatic gear lever/shifter when I try to start up. The clicking/tapping happens during setup key in position 2 as the car runs through it's diagnostic sequence.

Has anyone had this experience? Is it linked to the canbus/electrical issues or a seperate switch/connector issue physically linked to the shifter. The lever physically taps suggesting a servo driven repeating failed attempt to do something. Then diagnostic lights go on, and I'm stuck in 3rd gear limp mode.

Any suggestions? Havent removed unit covers yet, but that's my next move, alongside checking major electrical connections.

There's a shift lock solenoid that's activated by the brake pedal and this is what may be what's causing the "tapping", one tap should just happen when the brake pedal is depressed. The brake pedal switch is an input to the CEM and the CEM sends a signal to the GSM (gear shift module) which activate the shift lock solenoid. The ways it's supposed to work is the solenoid is activated when the brake pedal is depressed so you can shift out of park. If the solenoid is switching on and off then the there's a problem with the GSM, or CEM or power to the modules. Possibly he brake switch or solenoid but less likely I would think. If you can duplicate the problem does it make any different if the brake pedal is depressed when the problem occurs?

Post by **abscate** » 26 Dec 2020, 13:42

You need a healthy battery in any electronic vehicle like a P2

Troubleshooting with a weak battery is not productive.

greentrout · Post by **greentrout** » 29 Dec 2020, 05:21

Battery replaced.

Post by **firstv70volvo** » 29 Dec 2020, 08:46

greentrout wrote: ↑29 Dec 2020, 05:21 Battery replaced.

Battery just replaced or has already been replaced and still having the same problems?

If the battery has been replaced what is meant by it's only starting mostly with the battery pack? The new battery is not able to start the car without help from another battery? Is it due to a very long cranking time because the car isn't starting? Do you have a meter to check voltages? Battery voltage and alternator output should be checked. More details would help.

greentrout · Post by **greentrout** » 29 Dec 2020, 11:41

Sorry, I should have been clearer. I have just replaced the battery. The last one wasn't holding charge long enough to do any significant snagging before the voltage, as read by vida, would drop to c. 8ish. I'm planning to remove and clean the connectors on the CEM tomorrow.

Will update once I've had a go at that. The high speed canbus is down too, vida not recognising ecm tcm or bcm. The issues are intermittent so a broken wire, poor earth/short circuit or corroded connector are all possible causes. I found another thread here that seemed to address that, but the clicking at the gear shifter seems a central issue for me. I suspect that of draining power and adding to my problems, so I may need to resolve that first.

Additionally, there is an aftermarket Parrot bluetooth handsfee unit connected behind the cd radio unit. That starts up as soon as the ignition is turned to 2, so could well be another additional power leech. I plan to disconnect that too.

So a bit of a muddle, but I'm hopeful that if I work through things step by step I may, with some helpful guidance, save the old XC from the scrapyard yet

Post by **firstv70volvo** » 29 Dec 2020, 18:23

greentrout wrote: ↑29 Dec 2020, 11:41 Sorry, I should have been clearer. I have just replaced the battery. The last one wasn't holding charge long enough to do any significant snagging before the voltage, as read by vida, would drop to c. 8ish. I'm planning to remove and clean the connectors on the CEM tomorrow.

Will update once I've had a go at that. The high speed canbus is down too, vida not recognising ecm tcm or bcm. The issues are intermittent so a broken wire, poor earth/short circuit or corroded connector are all possible causes. I found another thread here that seemed to address that, but the clicking at the gear shifter seems a central issue for me. I suspect that of draining power and adding to my problems, so I may need to resolve that first.

Additionally, there is an aftermarket Parrot bluetooth handsfee unit connected behind the cd radio unit. That starts up as soon as the ignition is turned to 2, so could well be another additional power leech. I plan to disconnect that too.

So a bit of a muddle, but I'm hopeful that if I work through things step by step I may, with some helpful guidance, save the old XC from the scrapyard yet

If you're still (with the new battery) getting the click/tapping in the gear shift when the key is in position 2 I'm wondering what's going when this is happening. When this is occurring does it change when the brake pedal is depressed vs when it's released? The brake pedal switch signal is sent to the CEM, the CEM sends a signal to the Gear Shift Module and the shift solenoid should activate and let you shift out of park. It just sound like the solenoid is turning on and off, but why. CEM acting up, relay, gear shift module? Because VIDA is not seeing the BCM, TCM or the ECM I would suspect the CEM or the power/ground going to the CEM. You said the problem is intermittent, when things are working does the car run and shift okay, like the BCM, TCM and ECM modules are okay?

: Inkedshift lock_LI.jpg (646.15 KiB) Viewed 1519 times

greentrout · Post by **greentrout** » 02 Jan 2021, 03:12

Audible tapping can be felt at the gear shifter when the gear shift is in Park either when ignition at position 2 or when the car is started. The tapping stops if you depress the brake pedal and/or shift to R N or D.

Tapping restarts when you return the shifter to park.

GT