97 Mercury Sable - No Radio when in (R)

[kevinloose]

My 1997 Mercury Sable GS (AUTO/12V) has keyless entry system and power trunk. Only have 56K miles on her and she runs great. But recently, I just stated experiencing a weird issue. When I shift my car into reverse, the radio goes off until I put it back in Drive/Park. I notice a clicking noises, sounds like a relay clicking twice. Clicking which sound seems to be coming from the location somewhere right above brake pedal. Everything is STOCK including the radio, the oval AM//FM Cassette Radio w/CD Control options and manual climate controls.

Anyone ever had a similar problem. I WANT AND NEED TO RESOLVE BEFORE INSTALLING THE NEW 2-WAY AFTERMARKET ALARM w/REMOTE STARTER.

[schi711]

Check the wiring harness connector at the transmission neutral safety switch.
Open the hood and look towards the transmission and you should see half moon shaped switch with many wires coming out in a bulk connector. Either the switch is faulty or the wiring insulators have worn off and shorting out.
Try wiggling the harness first.
Do you also loose power steering assist at the same time?

[kevinloose]

Yes, I do loss the assistance of my power steering when the transmission (auto) is placed in (R) reverse, but only after hearing the clicking noise under dash which seems to be relay(s).

This problem had a related issue(s) that I was able to troubleshoot and fix a couple months ago. The accuracy of the column shifter PRNDDL Black Needle indicator was off by one step. (Example: When placed in (P) park, the dashboard showed (R) reverse. After troubleshooting, I was able to find that the one of the plastic cable adjustment guides had broken off. It was Located on bottom of shift column near main starter wire harness. I was able to fix the the plastic guide and properly adjust the indicator to show the actual gear status. I can only remember the loss of power to the radio periodic, since making sure the car was in the correct gear before driving was more important.

I am going to try a few things and troubleshoot today once I have someone on hand to help out.

Thanks for your input, I will check the Neutral Safety Switch harness for any type of wiring issue. I think the switch is working properly due to the fact the car only when auto transmission is in park or neutral.

Once again, thanks for your assistance. I will post all progress or updates.

~K~
kevinloose@yahoo.com

[schi711]

Kevin,
I am almost positve that you have an internally shorted neutral safety switch after your description. The clicking noise may be the relays cutting on and off while the short is present and it is feeding back to the relay box under the dash. Eventhough you say the vehicle starts only in park or neutral, some how the reverse circuit is feeding undo current to other circuits.
Unfortunately I am unable to send you a wiring diagram but on the n/s switch connector pin #11 is the reverse circuit and 12 is the starter relay circuit.
The clicking you hear is the starter relay and the reason why the radio cuts out is because you are simulating a start condition. Remember that the radio cuts out when you start the vehicle under normal condition?
Some how the switch is feeding current to the starter relay.
In short, replace the n/s switch.

[schi711]

Kevin,
The correct part name is called the transmission range sensor. Depending on the transmission you have it could be an eight or 12 pin design.
Should cost around $85 - 100.00