Originally Posted by
wrinklearthur
Wipe the wire at the glow plugs clean with some methylated spirits, check the wires colour and the trace along with the size of the wire, should be black with yellow trace.
for the direction it then travels to the relay ( part number PRC 6913 ), a clue can be the way it curves as it enters into the wiring loam.
The Glow plug timer relay is supposed to be mounted, under bonnet centre skuttle area.
The other thinner wires are ;
1. ( WR ) White-red trace, switched by ignition switch, starter position
2. ( YB ) Yellow-black trace, supply to cold start warning light
3. ( W ) White, switched by ignition switch, run position
4. ( B ) Black, earth path for the glow plug warning lamp
The two thick wires are ;
5. ( N ) Brown, from battery
6. ( BY ) Black-Yellow trace, switched wire from relay contacts going to the glow plug wire ( YB ) Yellow-Black trace.
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