Disco 1 cruise control

Hi all got issue with cruise control on 300tdi can anyone help, have replaced all vacuum pipes adjusted kickdown cable ran electricity tests on module connector as follows all with switch on and transport in drive, main power 12 volts secondary power 12 volts brake pin 12v set /+ 12v speed - 12V override vac pump with jumper wires pump runs bellows contract fully vss 9.4 to 10.5v depending on speed speedo working fine with bellows contracted push brake bellows open replaced ecu still won't work all ideas gratefully received

If your electrical tests as listed below have passed then your issue is mechanical.

Electrical test taken at the Cruise Control ECU electrical connector.
Ground Test - From pin 8 (black wire) on the cruise control module plug perform a continuity test to good chassis ground.
Main voltage test - With ignition & cruise control system on, transfer in high (non diff lock) & auto box in 'drive' connect volt meter between pin 8 (black wire) and pin 10 (white & yellow wire) you should have battery voltage if not check fuse.
Secondary voltage test - Connect volt meter between pin 8 (black wire) and pin 9 (Purple & Green wire) you should have battery voltage if not check lock out relay or gear selection switch.
Brake Pedal Test - Connect volt meter between pin 8 (black wire) & pin 5 (green & purple wire). Press the brake pedal, you should get battery voltage.
Steering Wheel Set / Accel Test - Connect volt meter between pin 8 (black wire) & pin 3 (red & white wire). Press the Set / Accel button, you should get battery voltage.
Steering Wheel Res / De-accel Test - Connect volt meter between pin 8 (black wire) & pin 4 (blue & white wire). Press the Set / Accel button, you should get battery voltage.
Vacuum Pump Test - Using a jumper wire connect pin 10 (white & yellow wire) to pin 1 (white & blue) this provides power to the pump. Then using a jumper wire connect pin 6 (black & yellow) AND pin 7 (black & red) to pin 8 (black wire). This should energise the pump & solenoid and the bellows should contract.
Speed Sensor Test - Connect a volt meter between pin 8 (black) and pin 11 (yellow & pink), drive the motor around the block, voltage should increase as speed increases.

Hi thanks for that thats the tests I used all passed when vac pump energised via multi plug engine revs rise as bellows contract am bit frustrated with this one!!!!!

Abbott said:

Hi thanks for that thats the tests I used all passed when vac pump energised via multi plug engine revs rise as bellows contract am bit frustrated with this one!!!!!

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Did you get this sorted?