Alloy Safety Interlocking Engine Start Switch – Bob Smith Please use this information and associated photographs in good faith. The Author does not guarantee the accuracy of the information and is not liable for use of said information. Ownership remains the property of the Author. The information and associated photographs must not be copied, profited by or used for commercial gain.

RLA Coil RLA 1 RLA Coil RLA 2 Oil pressure Switch –ve (to brown/white wire) Ignition +ve (to white wire) +- Start button With LED Permanent +ve (to red wire) To Starter (to white/red wire) 30A inline fuse Wiring schematic

Parts list Switch – Momentary starter – Pushbutton engraved alloy with blue LED – UR Motoring – RLA 1 – 5A 12Vdc DPDT – Maplin p/n JG66W RLA 2 – 40A 12Vdc SPST – Maplin p/n AR32K

Instructions Based on ’99 Chimaera Use 18 gauge wire throughout. Access required to top of dash (can be achieved with only the two passenger side nuts removed but be careful not to over strain things). I chose to fit the switch in place of the rear guard fog light switch so I also needed access to the radio console. The push button switch will need to be ordered with an additional power switch fitted; UR Motoring can supply. I moulded an additional aluminium outer ring for the switch so that it would better match the standard switchgear. This system employs an interlocking relay to prevent accidental starting when the engine is running and to maintain electrical power once the start process is underway. This utilises the –ve signal from the oil pressure switch to let the system know the engine is ‘not running’. Once the start process begins the signal from the oil pressure switch is overridden with a self latching switch within RLA 1. That way even if oil pressure is generated whilst cranking the engine the start system stays live. Once the engine is running the signal from the oil pressure switch prevents accidental operation. Connecting to existing wiring The oil switch signal wire is brown with a white stripe. This wire is within a loom that enters the upper dash near centre then feeds towards the off-side. There is a spare brown/white wire lying alongside this loom probably there for a remote oil light and is unused on my Chimaera. This wire terminates with a female miniature spade connector. Use this for the ‘oil pressure switch’ signal. All other connections are made in the steering wheel cowl. Link into the ignition loom on the nearside of the steering column. Wire colour codes Ignition +veWhite Permanent +veRed StarterWhite/Red Earthto chassis