Replaced my alternator today with a brand new one. When I started the truck up I'm still getting the flashing M & S lights. Been a while since I've replaced an alternator on my truck. Am I doing something wrong?

Thanks,
Scott

 

Low or bad battery will do that.

• Check your battery about an hour after you shut down should around 12.7-12.9V.
• Then check in the Am you still have close to that,some drop is expected but if you are around 12.4 -12.5 you should be good

If your Disco is like mine it will turn over and fire up at 11V, I have a slow drain I get past by hooking my on board charger up. But I was low one day and figured give a go nothing to lose and she fired right up but M&S lights flashed.

 

check all battery terminals for corrosion/tightness and hookups on new alternator.

 

Battery is about 1 yr old. Good connections and clean. Just got off the phone with my Indy Rover mechanic and he said could be XYZ switch. Taking it down to him tomorrow morning so he can get codes.
👿👿👿👿👿👿👿👿👿👿👿👿👿👿👿👿👿👿

 

First off... definitely find out what fault codes you are getting. Are you in Limp Mode? Is there flashing symbol looking like a crossed B for the gear selector? There can be 15-18 faults (mostly electrical) that trigger the flashing M & S lights and the Rover mech went straight for the xyz switch (P0705 code)? A new switch can be costly if that doesn't fix the problem.

Don't waste money on a new XYZ switch until you try this... remove xyz switch, disassemble it, clean it, relube it, reseal with new bolts, reinstall it and go for a run. There are several threads on the net where others have had success just by cleaning and resealing the XYZ switch.

 

According to the RAVE, there are 18 transmission faults that trigger the flashing M and S lights. All but one of them are supposed to also cause the Service Engine Soon warning light to illuminate, and 15 of the 18 also trigger limp home mode. Only one of the 18 indicates a problem with the XYZ switch. If the correct gear indicators are showing as you shift through PRND321 I'd be skeptical it's the XYZ switch causing the problem. So unless the mechanic finds P0705 (Gear position switch, incorrect outputs) there's no reason to rebuild or replace the XYZ switch.

 

I took it down to him this morning. When I got in it to drive it to his shop the S & M lights had disappeared. I have faith he will diagnose and fix the problem. He's been working on Rover's for 40+ years and I've been taking this particular truck to him for the last 10 year's. I expect him to call me tomorrow or the next day. I'll post what he tells me after I talk to him. 👍

 

I'm trying to diagnose this issue (intermittent on my 04)... can you point me at the spot in RAVE that covers these 18 faults? I have the individual pdfs; is it in the workshop manual?

 

@mln01 ... nm, found it.. pgs 44-19, 44-20 in workshop manual