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Discussion Starter · #1 · (Edited)
I got my 88 SZ Spur on jacks to do some tests on the leaky rack but it has decided not to start (or crank). Started fine last week. Battery is good. Lights all come on the dash, seat belt alarm blares, but won't do anything else. There is a click coming from the fuse box (near the interlock relay area), but no click coming from the relays in the hood (i.e. the starter relay). I changed over the interlock fuse with the radio, but no luck. Changed the Starter relay with the wiper relay, but also no luck. Put the gear change fuse back in and moved it to Neutral and back to Park again. Still no luck.

Here's the diagnostics list I've pulled together from the forum, but could do with some answers on a couple of these, as well as knowing if there's anything else anyone can think of that I might be missing:

1. Check wiring and any fuse/ breakers to your starter solenoid (Q - where are the breakers located?)
2. Check the starter solenoid itself (Q - any good instructions anywhere to tell if this is defective?)
3. Check the starter motor wire contacts (Q - I'm having trouble seeing where the wires connect to the solenoid. Can anyone help me understand where these actually connect?)
4. Check the ignition switch coupling (Q - where is this located?)

Q - Shouldn't there be a clicking sound coming from the Starter Relay? If not, why wouldn't there be?
Q - Anything else I can check?

Would be super grateful for any answers so I can get back to my original rack problem before this one added to the list.

Thanks all.
 

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Discussion Starter · #3 ·
Is it the start inhibit relay that's clicking?
No. Nothing on that relay board is clicking. The only clicks are coming from the relays under the fuse box (i.e. around the interlock & radio relays). The Starter, Starter Inhibitor etc are silent.
 

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Anyway, start with checking fuses B5 /F2, B3/F1 and "memory" fuse at luggage compartment. Check for tight sockets and voltages at both end of fuses.
At rrtechnical.info site is a manual TSD4701 that covers 88 models. Section "7" is for starting system. The Rolls
 

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Discussion Starter · #5 · (Edited)
I tested all the fuses and relays and they all look good. I checked both the coils and the connections on the relays. Looks like I'm now onto the starter and/or the ignition switch coupling before going through the wiring.

Couple of new questions:

1. Does anyone know if the starter on these cars typically has a stub on the end of the spindle I could manually turn to see if the pinion has got stuck in the flywheel (and if so, what's the best direction to approach it from)?

2. How easy is it to change the starter motor on these cars if its on jacks (vs on a lift)? I can get the exhaust removed easily enough, but need to know how accessible it is to the three connection bolts themselves without disassembling other pipes.
 

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OK. You checked fuses that they are tight in sockets and visually, that they are not burned-out. But did you measured voltages while ignition was turned-on? Most fuses have contacts available from outside - connect voltmeter probe to it (one to it, second to ground). Sorry, for stupid questions, but it is needed to know what exactly you do, what were results of tests and where your knowledge&skills end, if we are to help. Next step will be to check voltages at relays sockets.

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Anyway, you can try this already, to fast check if starter is working... (be careful, remember about to put gearbox to "P" and even use handbrake, read "relays" section of 4701 manual, understand what is going-on in relay socket): engine will not crank at all - help please.
 

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I'm guessing you've knocked a wire off while underneath, worth a look eh?
Otherwise check for voltage at start relay and work back.
Mike
 

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DO you hear the fuel pumps bzzzzzzzzzzz for few secs when key on ACC ?
If car does not crank at all, are you sure you battery did not collapse , even if new ?
If not enough amps, you will not crank and new batteries can die in few minutes.

Check also ground on the car, if not tight enough or oxydated, it may be involved.

FInally, keep in mind ENgine Management Relay which might be involved, although I think on some car it should crank but not start.
 

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Discussion Starter · #9 ·
Thanks for the ideas folks. I checked resistance on the fuses, not the voltages. Going to go back to square one and start afresh with this nice longer list.
 

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DO you hear the fuel pumps bzzzzzzzzzzz for few secs when key on ACC ?
If car does not crank at all, are you sure you battery did not collapse , even if new ?
If not enough amps, you will not crank and new batteries can die in few minutes.

Check also ground on the car, if not tight enough or oxydated, it may be involved.

FInally, keep in mind ENgine Management Relay which might be involved, although I think on some car it should crank but not start.
The fuses might be fine, but there could be a high resistance connection between the fuses and fuse holders. I found a couple in my Spirit that were dropping a couple of volts. Simply removing the fuse and reinserting them was enough to clean the connection.

Also, check to see if someone might have replaced one or more fuses, in the fuseboard, with inline fuses, and located them behind the fuse panel. In my care, I found 4 such inline fuses, one of which supplied power to the fuel pumps. The fuse had overheated at one of its connection.
 

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Discussion Starter · #11 ·
This is the first time I've done electrical diagnoses on a car so you'll have to excuse any totally dim mistakes I may be making here. Got a couple of further questions I could do with some help with if anyone has time. Here's what I've learnt so far:

Symptoms:

Turn key from Run to Start, engine doesn't start, dash lights come on, only clicks are coming from the relays in the glove box. No audible clicks are coming from the starter relay bank or the starter motor/solenoid. Fuel pump does not buzz.

Tests and Discoveries (based on some hopefully correct assumptions i could do with getting some verification on):

1. Battery - voltage shows 12.48V. No change when crank attempted. CCA rated at 800 CCA, shows 799 CCA when tested with a CCA measurer.
2. Battery earth strap connection - cleaned and reconnected the battery earth cable to the body and checked resistance at each end which was 0.00, so assuming this cable and body connection is okay.
3. Fuses - all fuses look visibly okay, have both 12+V at each end, and have 0.00 resistance running through them.
4. Relays - when connected to a power source, all relays click shut/open okay when connecting 30-87 connections, and also have 0.00 resistance when connecting 85-86 connections at the same time.
5. Gear change selector - moved from P to N and back again without any change in symptoms.
6. Battery Master Switch - Turned off and on, with no change in symptoms.
7. Power to Starter Relay - I figured since there is no clicking coming from the Starter relay board that it might be worth checking power getting to these first before raising the car and checking the starter/solenoid. This is when my confusion/interpretation of things starts my head spinning. I connected a light tester to make some tests on the relay connections after connecting it to the earth point on the body at the starter relay earth.

Q1 - I'm making an assumption that these are the correct relay connections, but I've found opposite information on the interweb after lots of googling, so hoping someone can confirm/correct me here -

85 = 12V connection from switch
86 = switch circuit to ground
87 = 12V connection from battery
30 = 12V output to component

are these correct?

I grounded one end of the light probe and then connected the other end to 87 in the starter relay. Got a light, which I think means there is a power from the battery to the starter relay.
I then had a helper turn on the ignition to Start and inserted the probe into 85 and then 86, but the test light did not lit up.

Q2 - If this relay was receiving a connection from the ignition switch, wouldn't one of these have lit up the test light?

8. Power to next relay after the Starter Relay in the circuit - I made (possibly incorrect assumption) that there may be power going to the starter relay but there's no connection from the ignition switch when powered. I then followed the wiring diagram from connector 85 on the starter relay back to what appears to be the Warm Up Regulator Inhibit Relay to conduct a test on this relay. This is when things got even more confusing.

TSD4701 Section 7-8 (Starting System) shows this relay under the steering wheel (Images 1 & 2).
TSD4701 Section 4 (Relays) shows a completely different set of relays under the steering wheel (Images 3 & 4 below).

Img1 - TSD4701 Section 7
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Img2
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Img3 - TSD4701 Section 4
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img4
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Q3 - where actually is this relay on an 88 Spur, and why would these diagrams show different things in the same Workshop manual in different sections? There maybe an invisible relay bank I'm not seeing under the steering wheel but I certainly can't see one. It looks in the electrical manual like these under steering wheel bank are reversed between a LHD and RHD car, hence I'm assuming is in fact this relay is there, that it is the most outboard one.

Assuming the left hand most relay (this is a LHD US car) is in fact the mysterious Warm Up Regulator Inhibit Relay, this relay's seats had no power going to any of them (85.86,87,87a, or 30) with or without the ignition switched to Start. The removed relay when connected to a power source clicked shut/open okay when connecting 30-87 connections, and also have 0.00 resistance when connecting 85-86 connections at the same time. This indicated to me that the relay is okay, but there is no power to it, which left me scratching my (already spinning) head even further.

Q4 - This Warm Up Regulator Inhibit Relay in the electrical diagrams (Img 5 below) shows with no 30/87 connection needed, and in fact only shows a wire going to either the 85 or 86 terminal. What would be the point in this in having a relay that doesn't create or bypass a circuit connection? If this is the case, how does it even get power (to which terminal???)?

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I might be doing this all wrong, but would appreciate any help with these questions anyone might have to correct me before I go any further (in the wrong direction). Hoping I'm not going completely barmey.
 

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Are you saying all your warning lights light up when turn to start position?
This is what happens if not in p or n, does your gearbox actuator actually move when ignition is on?
Mike
 

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85 = 12V connection from switch
86 = switch circuit to ground
87 = 12V connection from battery
30 = 12V output to component
Not sure. 4701 and just googling for "relays connection" say, that:
coil: 86 is +12V from switch, 85 is its ground,
load: 30 is +12V, 87 is a load connected then in-line to the ground (when coil is energized),
OR 87a is a load connection (when coil is in idle state, not-energized).

30264
 

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If relay is energized, you should have 12V between 86 & 85 (coil) and 87 & 85 (load, supposed, that 30 is powered and relay is mounted in socket).
 

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Q3 The manual covers many models and model years, sometimes LHD/RHD cars too. At the beginning of each section is a table that say which diagram to use to which model & year. I suppose, that pages 7-8 and 7-9 are concerned at your car.
 

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I believe, that both starter and inhibit relays should be under the hood, on the right side (passenger side for LHD cars), in the wiper motor area.
 

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Inhibit relay disconnects starter circuit (and some others?) when something is wrong, or just when engine is running. So, IMHO, it is de-energized in normal state.

When the key is in "start" position (starter on) there should be voltage in the socket connector 87a (huh, or 87?) of inhibit relay (relay removed) - note how it is drawn at diagram. This relay is controlled by electronic module, so there could be no real ground at any connector(!).

Then, the same voltage should be available (when key is in "start" position!, and inhibit relay in its socket) at gear selector and then gearchange actuator (if P or N), and then should return to starter relay connector 86.
I believe, you can check continuity of this circuit with ohmmeter, by measuring between connector 30 of inhibit relay socket and connector 86 of starter relay socket (both relays removed), with a key at "run" position ;). Check if there is a reaction for various positions of gear selector.

As we mentioned earlier, you can turn-on starter in any moment by shortage of 30 & 87 at starter relay socket. But before you decide to do that, make sure twice, that the gear is in P and hand brake is issued (be careful).


Anyway, when you turn ignition on, do you hear for one or two seconds that fuel pump is working??
 

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Another interesting thing is a "cranking interlock relay" (41 at diagram), but I'm not sure how is its role... possible it gives more current to starting circuit while cranking??
 

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Discussion Starter · #19 ·
Are you saying all your warning lights light up when turn to start position?
This is what happens if not in p or n, does your gearbox actuator actually move when ignition is on?
Mike
Not sure. 4701 and just googling for "relays connection" say, that:
coil: 86 is +12V from switch, 85 is its ground,
load: 30 is +12V, 87 is a load connected then in-line to the ground (when coil is energized),
OR 87a is a load connection (when coil is in idle state, not-energized).

View attachment 30264
Thanks szdowk. Looks like my google mechanic had his stuff the wrong way around. Not sure how to interpret this now that things are reversed from what I understood! Will start noodling this through.
 

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Discussion Starter · #20 · (Edited)
Are you saying all your warning lights light up when turn to start position?
This is what happens if not in p or n, does your gearbox actuator actually move when ignition is on?
Mike
Correct. All the lights come on. The gearbox actuator does move when the ignition is on. I can cycle between all the gears no problem.

The only thing I'd done since last driving it was to get the car on jacks so I could get the steering rack loosened off underneath. In the process, I removed the gearchange (F2/A6) fuse, just to make sure nothing moved when I turned the car on while it was in the air. The car won't start since I put the fuse back in. The rack work was fairly delicate, only involved a few bolts, and no electrics came close to my working area. Something smells like you're onto something here because this is the only related thing that has changed since the last drive (but I've got no idea what). The fuse housing & connections look sound and I tried changing the fuse a couple of times. All to no avail.
 
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