Designjet T1100 87:11 Fail nScan Axis Length: 1070368. Too SHORT

[theengel]

I had a customer who got 87 jams every time they loaded paper. If they loaded the paper and then turned on the printer, there would be some sort of 'paper loaded incorrectly' error.

I replaced the carriage unit (which includes the encoder sensor), the encoder strip, and the belt.

Still getting the same thing. When I do a Scan Axis test, I get through everything until after the left side bump. Then it says

ERROR: 87:11

FAIL Scan Axis length:
1070368. Too SHORT.
Check path is free.
Need mechanical repair.
Press any key to continue.

I can't think of what would cause this. The starwheel, formatter, and electronics module all test good.

[Kiran Otter]

Only thing I can think of is it might be the cutter. Try removing the cutter and testing it again.

I also had a case where a customer bough their own parts and it took me a while to realize they got the wrong encoder strip. It was just a hair too short and very difficult to install. The encoder strip should have a part number on it so you can verify.

Kiran

[theengel]

The original encoder strip looked perfect. I only replaced it to eliminate it... I stole it off a Z2100 from the shop.

You're thinking the carriage is running into the cutter causing it not to be able to travel all the way left?

That might be something. On the left bump test in the scan axis test, it goes all the way to the left, and then it begins a "checking scan axis length" But the carriage stops just before it gets half way through and gives me the "too short" error. As if it was stopped by a paper jam. But I feel no resistance in the carriage sliding all the way back and forth... and it's already gone from one side to the other side. It makes no sense.

[theengel]

I wonder if there's a weak spot in the cables. I saw the Z2100 and T1100 have the same trailing cables... maybe I'll bring that with me to see if it's poor communication between the encoder sensor and the eModule.

[Kiran Otter]

Umm.. the encoder strip for the T1100 is a different part number from the one for the Z2100. HP wouldn't give them different part numbers if they were the same part. You might want to put the old one back in and see what happens.

Kiran

[theengel]

I'll probably do that, but the old one has all the same problems as the Z2100 one. I hate to put money into it that won't produce a solution. But maybe I haven't eliminated it until it gets a new one.

[wcanonw]

the original encoder strip looked perfect. I only replaced it to eliminate it... I stole it off a z2100 from the shop.

You're thinking the carriage is running into the cutter causing it not to be able to travel all the way left?

That might be something. On the left bump test in the scan axis test, it goes all the way to the left, and then it begins a "checking scan axis length" but the carriage stops just before it gets half way through and gives me the "too short" error. As if it was stopped by a paper jam. But i feel no resistance in the carriage sliding all the way back and forth... And it's already gone from one side to the other side. It makes no sense.

the part you removed from the z2100 is not compatible with t1100, check the service manual and compare their part codes

[wcanonw]

HELLO GOOD MORNING, HAVE YOU DONE EVERYTHING INDICATED IN THE SERVICE MANUAL ABOUT ERROR 87?

System Error: 87:YZ
Problem Description:
Problem finding the Scan-axis encoder reading.
Corrective Action:
Try the following:
1Upgrade the firmware.
2Clean the Encoder Strip.
3Replace the Encoder Strip. See Encoder Strip, spring and nut (T1100/T1100ps/T610) on page 6-96 or Encoder Strip, spring and nut (T1120/T1120ps/T620) on page 6-99.
4Replace the Carriage PCA. See Carriage PCA (T1100/T1100ps/T610) on page 6-177 or Carriage PCA (T1120/T1120ps/T620) on page 6-182.
5Replace the Trailing Cables. See Trailing Cable (T1100/T1100ps/T610) on page 6-102 or Trailing Cable (T1120/T1120ps/T620) on page 6-109

[wcanonw]

the part you removed from the z2100 is not compatible with t1100, check the service manual and compare their part codes

FROM THE HP DESIGNJET T1100 SERVICE MANUAL
Q6683-60242 24 inch
Encoder Strip (including Encoder Strip Spring and Nut) T1100/T1100ps/T610
Q6687-60094 44 inch




FROM THE HP DESIGNJET Z2100 SERVICE MANUAL
Q6675-60071 24 inch
Encoder Strip (including Encoder Strip Spring and Nut) Z2100/Z3100/Z3100ps/Z3200/Z3200ps
Q6677-60024 44 inch

[theengel]

The different part numbers do not necessarily indicate different parts. Like I said, I only did it to eliminate it as a problem. The original one looks perfect. When I line the two up, they look identical... although, the space between the lines can't really be measured. Anyway, if the problem had changed after putting on the new strip I would be suspicious of it. But both strips produce the exact same problem, and in the same places. I think there's something else going on.