anderssj

I'm still fighting a no start on my 1986 5000cstq. I've checked all of the fuses and have run a number of voltage checks from the ignition switch outwards.

So far, I have 12v at terminal 15 of the ignition switch in run and start positions. I also have 12v at terminal 46/48 of the fuel pump relay in run and start, and the auto-check button seems to work (good cycle ending with "OK").

On the other hand, while I have 12v at the ABS switch in run and start, I have NO power at coil terminal #15 or ECU terminal #35 in run or start. Also I get no engine warning light with the key in the run or start position (probably due to no power to the ECU). FWIW, I have checked the ground connections at the ECU and they're good.

Looking at the Bentley manual, the current from terminal 15 of ignition switch flows to the coil and the ECU (among other stuff) through "T35 wire distribution terminal 15" on AUX relay panel II.

What is "T35 wire distribution terminal 15," and where is AUX relay panel II? Is the panel under the steering column as shown in Bentley? This is a wire connection that can be disassembled and cleaned, correct? If not, Is it possible/advisable to run a "jumper" to bypass the T35?

Any advice, BTDTs, or suggestions on other possible causes and fixes would be GREATLY appreciated.

Thanks in advance,

Steve A-

yota-toy

what caused your car to not start ie: repairs, sitting too long, how did it run before this happened?

RussB

The auxiliary relay panel II is under the dash, but closer to the centerline of the car than auxiliary relay panel I (which is to the left of the steering column, beneath the dash and accessible via a small hatch panel).

In general, running your own jumpers isn't the way to repair electrical problems.

As I recall, the electrical volume of the Bentley shop manual, in its first pages, before the electrical schematic diagrams, contains a schematic layout drawing of the numbered junction points in the car.

anderssj

Thanks, I found it. Problem was a loose/corroded connection at the T35 wire distribution terminal. The BL/R wire to the ECU and coil was getting less than 1 volt. Took it apart, cleaned it up and both get a good 12 v. Another new ignition switch installed and everything seems good--well valves are a little noisy after sitting for 2 months, but it starts and no codes.

Thanks again for the help!

Best regards,

Steve A-

RussB

Congratulations on a job well-done!