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Discussion Starter · #21 ·
Well I cleaned up the starter and solenoid connections and disconnected/cleaned up the ground strap. Still no change. The starter does not click and there's no click on the starter relay bank either. Anyone got any recommendations on what to check next?
 

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Discussion Starter · #23 ·
Been snowed with work so progress is proving slower than I'd hoped. The battery was reading was very variable voltages so I did get a new one (no difference) and can now confirm that there is power from the battery to the starter, but no power from the switch to the solenoid. I guess we were heading in this direction anyway, but at least the starter is the least likely suspect right now. Will report progress on the other tests shortly.
 

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Hi again
Check F1 B3 and see if its the cranking interlock relay is clicking (2nd in from the left under the fuses panel), and check fuse 17 in the boot.
Mike
 

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Discussion Starter · #26 ·
Hi again
Check F1 B3 and see if its the cranking interlock relay is clicking (2nd in from the left under the fuses panel), and check fuse 17 in the boot.
Mike
Thanks Mike. Checked both of these and they seem okay. The cranking interlock seems to be clicking when I try and start as well.
 

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Discussion Starter · #27 ·
My first port of call would be to check that the neutral start switch contacts are closing when you shift into N.

View attachment 30289
thanks Jeyjey. Do you know if this switch behind or inside the actuator assembly? The assembly rods move back and forth when I change from P to N. is this indicative of the switch working?
 

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The NSS is inside the gearbox actuator and can be tested externally via the loom. Yours appears to be working.
 

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Hi again
Having printed off the wiring diagram and studied it for an hour lol
Try this, the start inhibit relay ( location by the washer bottle),
Remove relay and connect 30 to 87 in the socket , then try starting it ( make sure it's in p anyway).
Let me know what happens 😊.
Mike
 

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Discussion Starter · #30 ·
Hi again
Having printed off the wiring diagram and studied it for an hour lol
Try this, the start inhibit relay ( location by the washer bottle),
Remove relay and connect 30 to 87 in the socket , then try starting it ( make sure it's in p anyway).
Let me know what happens 😊.
Mike
There is no connector at 87 - only 87a. This looks a change-over relay. Any harm in trying this to 30 instead?

(sorry to have got you looking at this diagram as a homework assignment!)
 

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Sorry yes the normally closed 87a to 30 ,it's been a long day lol
I'm trying to eliminate the engine running sensor.
I have attaced the wiring diagram I beleive is the one for your car ok, relay 2 is the one I want to bypass .
Good luck
Mike
 

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Discussion Starter · #32 · (Edited)
Sorry yes the normally closed 87a to 30 ,it's been a long day lol
I'm trying to eliminate the engine running sensor.
I have attaced the wiring diagram I beleive is the one for your car ok, relay 2 is the one I want to bypass .
Good luck
Mike
Made a spade ended connector from 87a to 30 and...no change. Tried in Neutral as well just in case, but no luck unfortunately. Given that my electrical knowledge is amateur at best, here's some assumptions I'm making:

1. The interlock relay (41) is clicking, meaning the ignition switch itself is sending an outbound circuit in that direction, so the ignition switch itself is fine.
2. If connecting 87a to 30 on the Starter Inhibitor Relay (2) bypasses the ERS (which would otherwise energize it), then the problem lies with either:
a. the Neutral Start Switch on the column (25), or
b. the Neutral Start Switch on the actuator (29), or
c. the Warm Up Regulator Inhibitor Relay (21), or
d. the Distributor (33) has a fault somewhere

'If' the gears are changing fine and the actuator is moving the mechanism between P and N (another assumption since I can see the rod moving), then does that mean I can discard a. and b. above and that there is power getting to the Neutral Start Switches? If these assumptions are accurate (I might be missing lots here!), then we might be down to the Warm Up Regulator Inhibitor Relay (21) under the dash (god forbidding I'm not looking at valances and connectors between all these things). The distributor sounds like a whole new kettle of fish so it would be good know if I can discard that one somehow.
 

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Then the fault lies in the p/n circuit as we thought, as it's the easiest to get to take the cover off the steering/gear selector and see what voltage you have at the inhibit Microswitch ok
Mike
 

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Discussion Starter · #37 ·
Then the fault lies in the p/n circuit as we thought, as it's the easiest to get to take the cover off the steering/gear selector and see what voltage you have at the inhibit Microswitch ok
Mike
Checked the microswitch at 25 in the steering column. It showed 12V at each end when its engaged in P/N. I'm guessing this means it's okay and we're down to either:

1. The Neutral Start Switch at the Gearbox actuator, or
2. The ERS - this one's still up for debate, but both fuses going to (F1/B3 and F2/B5) have 12V at each end, and it still doesn't start even if we bypass it with the manual link between 87a and 30 at the Starter Inhibitor, so it may be reasonable that this is maybe okay, or
3. The Warm Up Regulator Inhibitor Relay - I tested this one on the assumption that if the NSS at the gearbox was working then power would get to it. The voltages showed some weird readings I'm not sure how to interpret, esp since the wiring diagram shows a regular relay but the feed/output going through the same connector:

30295


The readings don't make much sense to me though -

86 - 1.7v
85 - 8.2v
87a - 3.7v
30 - 11.1v

If the supply circuit is receiving/sending 8.2v at 85, is this the one on the diagram with the connections. If so, does that mean we have power coming from the NSS (meaning the NSS is okay)? Would a 4v drop imply a problem? If the feed/delivery to the starter relay is supposed to be going to 86 then we've got a 10v drop.

Does anyone have advice on how to get inside the gearbox actuator to the microswitch inside? Still not sure why this would send some voltage to the Warm up Reg Relay if it was connecting okay though, but a 4v drop implies a problem (maybe?).

I might be hitting the bourbon soon.
 

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Hi Again
Bottle of brandy later lol
I would use a test lamp for more definate results ok ( around 5-10w)
Look and see what you have at 18 and 27 ok (see pic)
I would start at connector 27 the white /yellow comes from the column switch ,the white/red comes from the gearbox switch.
both should light the test lamp when you try start (leave the link in bypasing the start inhibit relay)
good luck
Mike
30296
 

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Discussion Starter · #39 ·
Hi Again
Bottle of brandy later lol
I would use a test lamp for more definate results ok ( around 5-10w)
Look and see what you have at 18 and 27 ok (see pic)
I would start at connector 27 the white /yellow comes from the column switch ,the white/red comes from the gearbox switch.
both should light the test lamp when you try start (leave the link in bypasing the start inhibit relay)
good luck
Mike
View attachment 30296
Thanks Mike. Will check these out. I took this photo in Kathmandu a couple of years ago. It's reminding me of the electrics in my car for some strange reason....
30305
 
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