The engine starts with the cam retarded. As soon as oil pressure is established it pushes the cam into the advanced position. When the solenoid is energized it pulls a plunger that releases the oil pressure going to the advancer mechanism allowing the cam to retard for higher RPM operation.

If it is throwing a fault immediately after starting, I'd suspect a problem in how the ECU recognizes cam position, and not necessarily the function of the advance / retard mechanism. That said I dont recall the exact text of that fault code so dont hold me to it.

Applying power to the solenoid with the engine idling should make the idle quality noticeably worse if the cam is actually retarding properly. That is the first test I'd perform.

__________________

90 300TE 4-M
Turbo 103, T3/T04E 50 trim
T04B cover .60 AR
Stage 3 turbine .63 AR
A2W I/C, 40 LB/HR
MS2E, 60-2 Direct Coil Control
3" Exh, AEM W/B O2
Underdrive Alt. and P/S Pulleys,
Vented Rear Discs, .034 Booster.
3.07 diffs 1st Gear Start

90 300CE 104.980
Milled & ported head, 10.3:1 compression
197° intake cam w/20° advancer
Tuned CIS ECU
4° ignition advance
PCS TCM2000, built 722.6
600W networked suction fan
Sportline sway bars
V8 rear subframe, Quaife ATB 3.06 diff