The car had been sluggish when cold and not wanting to accelerate until after a mile or so when it had warmed up, so i ran a diagnostic with my Crypton ACT, the engine was up to normal working temperature. It said the PTC heater was not present.
I let it cool down and did some investigation checking the continuity of all the cables in the loom. I had 12v to the relay coil in the Relay Module but it was not energising. The earth cable for the relay to the ECU (pin 6)was checked and found to be good. I supplied my own earth connection to the relay and it energised, proving that the relay was good. Could it be a problem within the ECU?
While checking cables I tested the Lambda heater and found this was also not getting any voltage from its relay. Again it had 12V to the relay coil but was not energising. I checked the continuity of the relay earth to the ECU (pin 36) and all was good. Supplying a separate earth path for the relay and it energised. Again is this a problem within the ECU and should I be sending it away to be tested ?
The ECU earth was also checked for continuity, but if there was an issue there I guess the engine would not run at all.
To test the Lambda output is it possible to disconnect it from the main loom plug and check it with a voltmeter or must it be in circuit. The reason for asking is while carrying out the diagnostic test I had the following reading - Lambda 703mV, the idle was erratic between 840 - 860 rpm and the timing would not settle being between 15 - 18 deg. The fuel trap and all the service pipes have been replaced.
I'm hoping that somebody with more experience than me can help with a way forward.
Thanks in advance
Dave