In addition to these errors below check the pico fuses on the DSP board. Tac-50 is the multibus system and uses 99.9% of T4 Errors.

102 T4 ONLY. Loss of DSP and CPU DPRAM communications. The CPU pulls SAF3 and the DSP pulls SAF1 and SAF2 to shut down the car until communication is re-established.

Check +5V output on DSP

103 T4 ONLY. Incorrect checksum on DPRAM data received from the DSP. The CPU pulls SAF3 until good data is received.

116 T4 ONLY. SAF1/SAF2 cross check error. If either the DSP or the ETSDL system indicate that they have opened the safety string and the CPU reads both SAF1 and SAF2 closed, this error is logged and the CPU opens SAF3. SAF3 is automatically closed if the condition is corrected.

Defective DSP card

Defective PMI #1 card

Loose cards in Multibus rack. Reseat cards.

170 EN-81 ONLY. Door Zone Control Monitor error. The DZCM input
is stuck while at a floor. Safety string is opened VIA SAF3 and a power cycle is required to close the safety string.
(Effective V20R0F)

The DZCM input module is bad.

The DZE1 or DZE2 output module is bad.

PTO or DZC relays bad.

171 EN-81 ONLY. Door Zone Control Monitor Rear error. The DZCM input is stuck while at a floor. Safety
string is opened via SAF3 and a power cycle is required to close the safety string. (Effective V20R0F)

The DZCMR input module is bad.

The DZE1r or DZE2r output module is bad.

PTOR or DZCR relays bad.