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Discussion Starter · #43 ·
What's happening? Fixed it yet?馃憤馃槉
Got a little side tracked with life over the last week (including fixing my daughter's Camaro). Got a couple of days off and planning on getting back to it tomorrow. Your idea of checking the 27 socket is definitely the first think I'll be tackling. From there the ERS will be the next thing to check. The Cranking Interlock Relay is defo working and clicking happily in there, but no power is flowing from this (through the ERS) to energize the Starter Inhibitor Relay. I'm kind of thinking that if the ERS was fine then the SI Relay would still click because it would be energized. Will report back soon!
 

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So if a relay is clicking, then the relay is faulty on it's secondary circuit (contacts are shot internally), and/or the the source on the secondary circuit has no voltage.
Have you actually checked the relay for continuity when it's switched of and on ?
Just because a relay clicks doesn't mean to say that it isn't faulty.
 

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Discussion Starter · #45 ·
So if a relay is clicking, then the relay is faulty on it's secondary circuit (contacts are shot internally), and/or the the source on the secondary circuit has no voltage.
Have you actually checked the relay for continuity when it's switched of and on ?
Just because a relay clicks doesn't mean to say that it isn't faulty.
I took the relay out, connected it the battery (it clicked) and checked resistance between 87 and 30 (which was 0). Hopefully that means it's okay. I swapped it out with another one as a secondary test, but ended up with the same result.
 

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Discussion Starter · #46 ·
Think I made a step forward today. I couldn't find the gearchange plug and socket 4 way connector (27) behind the ERS for love nor money so figured I'd try something else. Not sure if this was the smartest thing to try, but I made a connection between 87 and 30 on the Starter Relay. I figured that if the car cranked then this would at least prove that the starter motor isn't the root issue, and if it started up AND ran then that would prove that the ERS was operational as well, since (from what I can interpret from the electrical diagram) if the ERS was faulty then it wouldn't send current to the distributor and there wouldn't be a spark. The major risk (other than some electrical damage this might cause that I couldn't think of) was that I needed to employ the help of a partially competent teenager on the brakes to ensure that if the car started in gear that it wouldn't lurch forwards into a nice shiny Jaguar parked in front of it.

Sure enough the engine cranked AND started (and fortunately didn't move). With 12V on each side of the column neutral start switch and an operational WUR Inhibitor Relay, this theoretically boils the issue down to the Neutral Start Switch in the gearchange Actuator.

The one complexity this introduced that got me scratching my head was that the car started without the key even in the ignition (!). I've therefore got a couple of questions I'd love some help with:

1. Anyone know why the car would crank even without the key in? Shouldn't the circuit be open until the key is turned to start?
2. Anyone know where the electrical loom comes out into the car from the gearchange actuator ? Could do with knowing where this ends before I start ripping all the carpets out to disconnect it.

Thanks all!
 

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1. Anyone know why the car would crank even without the key in? Shouldn't the circuit be open until the key is turned to start?
Because the "key" turn on relay, which you shortened directly. The engine will not start without ignition powered up, what do other "key" circuit, but what is ommitable by shortening some other relays too. It is why people are using alarms and immobilizers.
 

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Does anyone have lhd component layout of starter system? All mine in tsd 4701 are rhd and section 7 is missing from tsd 4848.
Mike
 

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Discussion Starter · #52 · (Edited)
Looks like we're down to the two final suspects - gearchange actuator (and associated microswitches) or the Engine Running Sensor. I got a bit sidetracked after finding the Procedure in TSD4737 for testing the ERS. Turns out my interpretation of the starting circuit was slightly incorrect once I read this section, meaning the ERS could be a front runner here since the fuel pump isn't buzzing. I've got the fuse panel off and can get to the loom to disconnect it, but can't the darn thing disconnected despite a few hours of squirming around back there (yes, I have opened the fish hook locks on each side...) . Does anyone know if there is some RR special technique involved here (e.g. are the orange or yellow tabs some kind of lock?).

Automotive design Automotive lighting Auto part Technology Electrical wiring


Sorry for the amateur hour questions here folks.

馃う鈥嶁檪锔

Still hunting for Loom 27 Mike, but I'll find it eventually!
 

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Discussion Starter · #53 ·
Looks like we're down to the two final suspects - gearchange actuator (and associated microswitches) or the Engine Running Sensor. I got a bit sidetracked after finding the Procedure in TSD4737 for testing the ERS. Turns out my interpretation of the starting circuit was slightly incorrect once I read this section, meaning the ERS could be a front runner here since the fuel pump isn't buzzing. I've got the fuse panel off and can get to the loom to disconnect it, but can't the darn thing disconnected despite a few hours of squirming around back there (yes, I have opened the fish hook locks on each side...) . Does anyone know if there is some RR special technique involved here (e.g. are the orange or yellow tabs some kind of lock?).

View attachment 30413

Sorry for the amateur hour questions here folks.

馃う鈥嶁檪锔

Still hunting for Loom 27 Mike, but I'll find it eventually!
Ignore me folks. I unscrewed the ERS from its mount, flipped it around and a little leverage with a screwdriver did the job. Maybe some complete amateur like me will find this useful one day if they ever read this.

(but I highly doubt it)
 
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