p1395 code

[87 rebel]

I have a 1997 f250 4x4 crew cab i replaced the valve cover wiring harness, glowplugs and the glow plug relay about 5-6 weeks ago. It has been great until yesterday evening, when i started it up the check enging light came on so i checked with the scanner the code came up p1395. I had this before and now i am frustrated to have it back again so soon replacing those v/c gaskets are a pain!.. i hope the fix might be the glow plug relay??? anyone have any advice? i checked to make sure the connections were secure at the v/c and than cleared the code i hope it was just a fluke?

[pjwoolw]

Guessing you rig is a California truck?

[87 rebel]

yep cali truck bought right here in oregon brand new! guess that's what happens when you live too close to the boarder?
LOL

[pjwoolw]

Here is a pic of what the GPR and shunt should look like. If your shunt has been removed for whatever reason and the wiring to both banks of GPs are wired together without the shunt you'll see that code.

[87 rebel]

thanks! it has been replaced 2 times but the wiring is correct. i replaced the glow plug relay, the glow plugs, and the valve cover gaskets with the wiring and replaced the wiring plugs on the external and inturnal about 6 weeks ago. that fixed the problem and have had no check engine lights come on since, until the other day which i checked all the connections to make sure they were tight and cleared the codes. as of this morning i still dont have any codes but it is still making me wonder what the heck?????????

[pjwoolw]

The code may have been stored if you didn't clear it after your repair. When I was fooling around with mine awhile back that was the case.

[87 rebel]

p1395 code is BACK! checked the glow plug relay with a volt meter and it checks out good, my connections all look good cleared the codes and it came back the 3rd time i started it. something is wrong!!!!!! i just dont know where or what. anyone have any advise before i break down and take it to my diesel mechanic? I HATE to pay someone else for something i can do! !

[pjwoolw]

Here are some testing procedures provided by the amazing Rick. I'm sure he wont mind me borrowing them. Is the shunt in good shape. If they have a bend of crack in them that could be your trouble too. If so they are available from Ford.

This is from the manual: I don't know if it will help

S1 DTC P1391, P1395 — RIGHT BANK AND P1393, P1396 — LEFT BANK

Note: For running KOER glow plug monitoring self test, refer to Section 2C .
One of the above codes will set when glow plugs are commanded on for over 35 seconds and battery voltage is between 11.8v and 14v, with at least one glow plug not being powered.
Key off.
Measure voltage between large wire terminal Circuit 38 (BK/O) on glow plug relay and battery ground.

Is battery voltage present?
Yes No GO to S2 . SERVICE open in Circuit 38 (BK/O) or fusible links.
S2 CHECK FOR DTC P0380

NGS installed.
Perform KOEO On-Demand Self Test and Retrieve/Clear Continuous DTCs.

Is DTC P0380 present?
Yes No GO to S3 . GO to S8 .

S3 DTC P0380

DTC P0380 is set when the PCM detects a malfunction in the glow plug relay control circuit.
Possible causes:
shorted to power
open/grounded circuit
open fuse (F-Series — Fuse 22, Econoline — Fuse U)
worn or damaged glow plug relay
Key on, engine off.
Measure voltage at glow plug relay point B, Circuit 16 (R/LG) and battery ground. Refer to the schematic for location of circuits.

Is voltage present?
Yes No GO to S4 . SERVICE open in ignition power Circuit 16 (R/LG). If fuse is blown, CHECK for short to ground.
S4 RELAY COIL RESISTANCE TEST

Key off.
Disconnect the wire going to the glow plug relay, Circuit 1086 (P/O) point A.
Measure resistance through relay coil, between point A and Point B.

Is the resistance between 1 ohm and 8 ohms?
Yes No GO to S5 . REPLACE glow plug relay.
S5 CHECK SHORT TO POWER

Key off.
Install breakout box. Leave PCM disconnected.
Control circuit still disconnected from the relay.
Key on, engine off.
Measure voltage between test Pin 101 and battery ground.

Is voltage present?
Yes No SERVICE short to power. CLEAR DTC and RETEST. GO to S6 .
S6 CHECK SHORT TO GROUND
Key off.
Breakout box installed. Leave PCM disconnected.
Measure resistance between disconnected wire going to glow plug relay and battery ground.

Is resistance greater than 10,000 ohms?
Yes No GO to S7 . SERVICE short to ground. CLEAR DTC and RETEST.
S7 CHECK CIRCUIT FOR OPEN

Key off.
Breakout box installed. Leave PCM disconnected.
Measure resistance between test Pin 101 and Circuit 1086 (P/O) eyelet going to glow plug relay.

Is resistance less than 5 ohms?
Yes No REPLACE PCM. SERVICE open in Circuit 1086 (P/O).
S8 CHECK GLOW PLUG RELAY

The glow plug ON time is dependent on oil temperature and altitude. The glow plugs come on between 1 to 120 seconds depending on oil temperature and do not come on at all if EOT is above 55°C (131° F). Verify glow plug control ON time by using NGS PID GPCTM.
EOT temperature below 49°C (120°F).
Key on, engine off.
Measure voltage between center terminal of glow plug shunt and battery ground.

Is voltage present for at least 30 seconds?
Yes No GO to S9 . REPLACE glow plug relay.
S9 CHECK GLOW PLUG

Key off.
On the bank with the code, disconnect both connectors on the valve cover gasket.
Inspect both harness connector and gasket for a loose fit. If damaged, repair or replace.
Install Rotunda Glow Plug Injector Adapter 014-00935 or equivalent to the valve cover gasket.
Measure resistance between each of the four glow plug circuits on Rotunda Adapter and engine ground (clean off a spot on the high-pressure oil reservoir to ensure a good ground).

Is resistance less than 2 ohms?
Yes No For DTCs P1391 and P1395, GO to S11 .

For DTCs P1393 and P1396, GO to S12 . GO to S10 .
S10 CHECK UNDER VALVE COVER

Key off.
Remove valve cover and verify that the connections to the glow plugs are OK.
If OK, disconnect the suspect glow plug connector.
Measure resistance between the glow plug and engine ground.
Is resistance less than 2 ohms?

Yes No REPLACE valve cover gasket or UVC harness. REPLACE glow plug. CLEAR DTCs and RETEST.

S11 CHECK GLOW PLUG MONITORING CIRCUIT — DTCS P1391, P1395
Key off.
Disconnect all four valve cover connectors on both right and left banks.
Inspect both harness connector and gasket for a loose fit. If damaged, repair or replace.
Disconnect PCM.
Install breakout box. Leave PCM disconnected.
Measure resistance between all four glow plug circuits on the right bank and test Pin 9 on the breakout box.
Are all readings within 2 ohms of each other?
Yes No GO to S13 . SERVICE open between valve cover connector and PCM connector. VERIFY glow plug shunt nuts are clean and tight.

S12 CHECK GLOW PLUG MONITORING CIRCUIT — DTCs P1393, P1396
Key off.
Disconnect all four valve cover connectors on both right and left banks.
Inspect both harness connector and gasket for a loose fit. If damaged, repair or replace.
Disconnect PCM.
Install breakout box. Leave PCM disconnected.
Measure resistance between all four glow plug circuits on the left bank and test Pin 34 on the breakout box.
Are all readings equal and less than 2 ohms?
Yes No GO to S13 . SERVICE open between valve cover connector and PCM connector. VERIFY glow plug shunt nuts are clean and tight.

S13 CHECK GLOW PLUG MONITORING CENTER CIRCUIT
Key off.
Breakout box installed. Leave PCM disconnected.
Measure resistance between center terminal on glow plug shunt and test Pin 8 on the breakout box.

Is resistance less than 2 ohms?
Yes No GO to S14 . SERVICE open in Circuit 339 (GY).

S14 COMPARE RIGHT BANK TO LEFT BANK
Key off.
Record all readings. The circuits must be within 2 ohms of each other.
Measure resistance between all four glow plug circuits on left bank and test Pins 8, 9 and 34, then all four glow plug circuits on right bank and test Pins 8, 9 and 34.
Are all readings within 2 ohms of each other?
Yes No REPLACE PCM. SERVICE open in the higher resistance circuit. VERIFY glow plug shunt nuts are clean and tight.

S15 DTC P1397 SYSTEM VOLTAGE OUT OF SELF TEST RANGE DURING KOER GLOW PLUG MONITOR SELF TEST

Note: DTC P1397 will set if system voltage is above 14 volts or below 11.8 volts at any time during KOER Glow Plug Self Test. It may be necessary to raise rpm to maintain voltage. If unable to maintain system voltage, service as required according to service manual direction.

Perform KOER Glow Plug Monitor Self Test. With a digital multimeter connected to the battery. Maintain system voltage until test is complete.
Does P1397 still set?
Yes No GO to Pinpoint Test A1 . No concern located at this time.

[pjwoolw]

There is also a TSB on this issue.

TSB 98-15-1

[Desert Rancher]

Wondering if this ever got resolved? I know it's a year old now...

~DR