To SORN or not to SORN

Now that the summer is finished and the weather is getting poor the big decision for all kit car owners comes around.   Should you take the car off the road and do all those jobs that have been stacking up over the summer.  Or do you brave the cold weather and continue to drive the car over the winter.

My decision:    Keep her running and just wrap up warmly.

Dashboard Project - Phase Four

The next stage was covering the gear lever housing and transmission tunnel in vinyl to match, and I took the opportunity to fit a nice chrome surrounded gear lever mounting of a Ford Fiesta.

 

For my birthday I treated myself to a new set of warning lights that actually have the correct symbols displayed. So far they are: Cooling fan, Alternator, Oil Pressure and Indicators. I have also got ones for Headlight Full Beam and Handbrake Warning, which are still to be fitted. 


Status: - Getting there slowly, just centre console left.

Battery Isolation Switch

I got sick and tired of disconnecting/reconnecting the battery while I was testing the electrics so I fitted a Battery isolation switch.

For those that don't know, if you remove that red key the car is then completely dead electrically and will not start. It's official purpose is to make it more difficult to steal so that might come in useful if I ever have to leave it somewhere. 


Although you can buy those keys for £1.50 off E-Bay so I guess a professional thief would carry one around with him, 

But it would deter the casual thief and stop those people who think it is clever to reach in and turn on the hazard warning lights to drain the battery. 

Status: Complete

The Starting Problem

There are a few thoughts on why the engine struggles to crank when you try and start a hot engine: 

1. The engine itself ‘tightens’ up when it is warm, making it difficult to turn over. 

2. Advice on the forum is that the absence of a decent earth strap from engine to chassis can cause a voltage drop.

3. If the ignition advance is too much it would make it difficult to turn over. 

There is nothing I can about (1), and (3) is controlled by the ECU, so all I can do is fit a proper earth strap and hope it helps. 

Here it is: 

I also decided to add a voltmeter into the circuit so I could see if the battery was struggling. I didn't want it to be a permanent distraction so mounted it on the auxiliary electrical panel where it can easily be viewed when troubleshooting. 


As you can see, at 12.5V it is quite healthy. When the ignition is switched on it drops to 12.3V, which is fair. If you turn on a high-power system like the demisters or the headlights then it drops to 11.8V, not unexpected. Once the engine is running it shows 14.1V which means the alternator is charging it well. 

The only slight concern is that while cranking it initially drops to 9V before recovering to 9.8V. That is marginal. Something to keep an eye on. 

Update:   March 2014 - Now had a chance to try a hot start and everything was fine.  See "Sunday Run with Hot Start"

Status: Complete

The 'Electrics' Project - Services

The next stage was a list of all the electrical ‘services’, annotated as to whether they used a ‘direct’ 12V supply or an ignition switched 12V, whether they ought to use a Relay (and if so which one), and which fuse they used. 
 (Red is unknown)

Service	12V	Colour	Relay	Fuse
Demisters	Ignition		Yes – Relay 1	3
Fog Lights	Direct	Blue/Yellow	Yes – Relay 2	4
Horn	Direct	Purple/Black	Yes – Relay 3	1
Headlights (Main)	Direct	Blue/Red	Apparently none	1
Headlights (Dipped)	Direct	Blue/White	Apparently none	1
Cooling Fan	Direct	???	Yes - Relay at Front	11
ECU	Ignition	Green/Pink	Yes - Not found	?
Lamda Sensor	Ignition	Green	Yes - Relay 4	?
Fuel Pump	Ignition	White	Yes - Relay 5	?
Indicators	Ignition	Green/White	Yes – Flasher Relay	?
Hazards	Direct	Green/White	Yes – Flasher Relay	?
Sidelights	Direct	Red	No	4
Number Plate Light	Direct	Red	No	4
Reversing Lights	Direct	???	No	10
Brake Lights	Ignition	Green/Purple	No	4
Cluster Illumination	Ignition	Red	No	4
Instruments	Ignition	Green	No	2
Warning Lights	Ignition	Green	No	2
Wipers	Ignition	Blue/Yellow	No	?
Washers	Ignition	Green/Black	No	?

Instrument Panel Wiring
 

Just for completeness I figured out the Instrument Panel wiring:  (Blue means Not used, Red means don’t know)

Pin	Colour	Usage
White Plug
12	Red	+12V for Panel illumination
11	Blue/White	Headlight Full Beam Warning
10	Black	Earth for Headlamp Warning and Panel Illumination
9	Not Used	(ABS warning light)
8	Black/Yellow	Handbrake/Brake Fluid Level Warning Light
7	White/Green	‘S’ Connector on Temperature Gauge (Sender)
6	White	‘S’ Connector on Fuel Gauge (Sender)
5	Black	‘E’ (Earth) (Earth) for Fuel and Temperature Gauge
4	Not Used	(Diesel GlowPlug)
3	Not Used	(Washer Fluid Level)
2	Not Used	(Low Fuel)
1	Green	12V for lamps and ‘B+’ on Fuel & Temperature
Blue Plug
1	Black	Earth for Indicator Lights
2	????*	Indicator Lights
3	Not Used	(Windows ??)
4	Not Used	(?????)
5	Not Used	(Seat Belt)
6	?????*	From Negative Side of Coil (not connected on board ?)**
7	Brown/Yellow	Alternator Warning Light
8	?????*	‘E’ on Tachometer (from +ve side of coil)
9	?????*	‘S’ on Tachometer
10	White/Brown	Oil Pressure Warning
11	Not Used	(Rear Screen Heater)
12	Green	‘B’ on Tacho (12V ignition switched)

*      I will be able to complete the colour column when I remove the centre dashboard.

**    The wiring diagram says to connect to coil but on PCB on back of cluster it doesn’t appear to be connected to anything.

LAMDA SENSOR

Not something I have seen before so needed to figure out the wiring.  Seems it is:

Sensor	Engine Plug	Function
White*	Black (Earth)	Heater
White*	Brown/Blue (Power)	Heater
Grey	Green	Signal
Black	Grey	Earth

The 2 White wires are interchangeable

ECU

The Electronic Control Unit is a ‘black box’, but I did find a breakdown of the connections:

Pin	Colour	Function or Termination	Comments
1	White/Yellow	Coil -ve	Not Used
2	Pink/Blue	Stepper Motor Phase 2
3	Orange/Grey	Stepper Motor Phase 1
4	White/Pink	Feed from main ECU relay	-ve side of Switching Circuit
5	Not Used	Air Con Control
6	Not Used	Cooling Fan Relay
7	Grey	Lambda sensor +	Revised wiring extension
8	Yellow/Green	Throttle Sensor Supply
9	Yellow/Purple	Throttle Sensor Input
10	Pink	Diagnostics Output
11	Green/Pink	Ignition Sensing
12	Not Used	Electronic Tacho Output
13	Black/White	Immobiliser Control	Disabled
14	Not Used	??
15	Not Used	Air Con Control
16	Green/Black	Air Temp Sensor Input
17	Yellow	Engine Knock Sensor
18	Light Green	Lambda sensor -
19	Not Used	Air Con Control
20	Black/Purple	Fuel Cut off Relay Control.	-ve side of Switching Circuit
21	Yellow/Orange	Boost Purge Valve
22	Orange/Green	Stepper Motor Phase 3
23	Yellow/Green	Injector 1-4
24	Yellow/Blue	Injector 2-3
25	White/Black	Coil +	Actually to Coil -ve
26	Not Used	Cruise Control
27	Orange/Blue	Stepper Motor Phase 4
28	Brown/Pink	+12V Power	+ve Power circuit from Relay
29	Black	ECU Earth
30	Pink/Black	Engine Sensors Earth
31	Blue	Crankshaft Sensor +
32	White	Crankshaft Sensor -
33	Pink/Green	Coolant Sensor Input
34	Grey/Pink	Fuel Rail Sensor Input
35	Not Used	Air Con Control
36	Black/Green	Lambda Sensor	-ve side of Switching Circuit

 

LIGHTING CIRCUIT

Pin 30 on both relays get a permanent +12 V Power Supply from Fuse 1

Pin 87 on the relays goes to Main Beam (Blue/White) and Dipped Beam (Blue/Red)

Light Switch gets Direct Power from Fuse 1.  

Position 1 sends power to sidelights through (Red/Grey)

Position 2 sends power to High/Dip Switch which feeds Pin 85 of appropriate relay

Pins 86 get fed an ignition switched earth feed    (Apparently not, seems to be permanent earth?)    

Status:   Lots to do, I still have the following outstanding questions 

1.  Where is the relay for the Lamda Sensor Heater ?

2.  What are Fuses 5-9 for ? 
3.  Where are the fuses for the indicators and wipers/washers ?