Electrical gremlins

BX Tech talk
rutter123
Over 2k
Posts: 2150
Joined: Sun Sep 02, 2012 9:54 pm
Location: South Lincs
x 52

Electrical gremlins

Post by rutter123 » Wed Dec 09, 2015 11:28 pm

Low water and big red STOP lamp on rev counter not working, yet if i switch the headlamps on hey presto the warning lamps go out and the rev counter works. The water level is ok and the sensor is new, any ideas?
Can see no wiring faults and every checks out with a multimeter.
90 BX Tzd turbo 294k SORN undergoing major surgery
90 BX Tzd turbo estate 46k awaiting surgery
65 Peugeot Boxer Van the new workhorse
52 Toyota Rav4 180k Bulletproof Jap reliability

User avatar
Way2go
Over 2k
Posts: 7279
Joined: Fri Jan 13, 2006 3:15 pm
Location: RCoBerkshire
x 2

Re: Electrical gremlins

Post by Way2go » Thu Dec 10, 2015 12:22 am

The symptoms that you describe would suggest you have an earth fault, ie a missing (or high resistance) earth on one side of the rev counter and "STOP" light.

Most circuits on the BX are switched on the earth rather than plus and therefore when you switch on the headlights you are replacing the missing earth via the switch in some way. You need to check relevant earths on a resistance meter with one probe attached to a good and clean chassis point.
1991 BX19GTi Auto