One of the common failures of the LH ecu is a hybrid pcb that stops working. A common symptom is not energizing the fuel pump anymore (beside some other problems. Many times the car is flat bedded home. But this is not always necessary. If for whatever reason the fuel pump relay is not activated or is not working, here's my recommendation to bypass the relay and patch the situation ins the safest possible way to get you home.

Be aware: this is not !!!! a safe and proper fix, it is a get-me-home workaround.

It is almost certain that this problem will happen if your LH has never been rebuilt. We offer that LH rebuild service: Diag.htm


- test the relay by swapping it with the horn relay. Look up on your relay chart which that is. If the car starts and the horn does not work anymore you have found a defective relay. It happens.

- If the test still shows a not-running pump it is possibly a broken fuse #42 in a GTS Check your fuse map. You can test the fuse on the green-led fuse tester (part of the Ezk relay)

- if all seems ok, it can still be a broken fuel pump. That is not so easy to check. It takes removing the cover of the pump area i the back, and use a test light to see if power reaches the pump., If so you may have a defective pump.

- take relay (XX at MY 1987, XXVI from 1990 onwards) out, connect socket terminal 86 with 87.  This connects the ignition-key switched 12v supply from power rail 15 to the pump directly. It does make perfectly sense to fabricate a little wire with two AMP prongs and put that into your glove box next to the flashlight and the 12v test light you (should) have in there. Be very careful not to make a mistake on which pin is 86 and 87 in the relay socket. If in doubt, use the alternative as below! You risk damaging the LH ecu !!!

- There is another option (XX at MY 1987, XXVI from 1990 onwards): connect permanent 12v power supply (rail 30) to the pump directly. so bridge 30 and 87. This makes the pump run until the battery is dead or jumper removed. This option is safer as you can easily identify the 87 and 30 pins because of their orientation. Some pictures by Tony Harkin say it all:


U25 is the 12v power that feeds the pump. (GTS, YMMV)